Page 1 Aug/Sep 2017 Volume 4 Issue 2 The Taboo of the Flight Review Cones of Sadness Pavement Strength Planes that Flopped The X Files An Airmanship Refresher?
Page 2 From the President Greetings Members, This is shaping up to be a great year, as there has been much progress in both the club and flying school activities, and there is also a lot of developments and opportunities in the pipeline for the future, some possible, some likely, and some, well, let s just say, testing the waters. More will be said about these as they evolve. No doubt most of you have been enjoying the efforts of our tireless Club Committee, and on behalf of the Board of Directors, I would like to express our gratitude for their dedication and efforts. The Breakfast with Victor event was a resounding success, and so much so that a third session had to be organised for that day due to the large number of participants. The Coober Pedy Air Safari in the second week of August is also shaping up to be a great success, and it offers something for everyone. For the inexperienced among us, it is a great opportunity to treat this as a long cross country training flight, as you will be briefed and followed every step of the way in a group environment, and will have ready access to the wealth of knowledge some of the more experienced participants will bring. For the passengers, it promises to be a wonderful opportunity to experience the great Australian Outback in a way that can only be done in a light aircraft, as well as enjoy the social aspects of this event. For the experienced among our community, you already know what s in store, and I am sure you are looking forward to it if you are able to make it. The college side of the business has settled into the current course of some 25 new students. The new cohort has brought a buzz to the place and has fitted in quite well and quite quickly to the environment, and all are eager to learn and face the challenges and rewards that a career in aviation will bring to them. After completing their initial five weeks of theory, they are now commencing their flying sequences as they work towards their RPL as the first step. We wish them all the best in their endeavours. Another great newsletter in this edition, and I thank the contributors, Mitch Anderson, Anthony Coleiro, Bill Cooper and Justin McCoy for their well written and interesting articles. One a somewhat blue note, I will make a special mention of Paul Blackshaw s final contribution as Safety Manager. Paul s development of SFC s Safety Management System (SMS) over the past couple of years has been peerless and we truly have an SMS that is the envy of every flying organisation at YSBK (and beyond) and something that SFC should be (and is) very proud of. We are indebted to his tireless efforts in bringing it to what it is today. Paul s successor will have massive shoes to fill. Once again, on behalf of the Board of Directors, I would like extend a profound thank you! Until next time, safe flying! Amir Hyster President
Page 3 Coopers Corner Pavement Strength What s this (above) is part of the ERSA entry for YSBK, Bankstown Airport, giving information on the dimensions and pavement load-carrying capacity of its runways, to assist pilots planning to operate there. (See Appendix A. Page 9 for explanation of terms). This document discusses how to check that a runway can support your aircraft. Some time ago, a Boeing 707 made an emergency landing at Darwin airport. That was uneventful and the aircraft was taxied to apron parking. The next morning, the aircraft main landing gear was found to have sunk to the axles in the substrength pavement: The aircraft was too heavy for the pavement. This had been an emergency, so the arrival was justified, but.. Q. How is this issue of matching aircraft weight to pavement strength routinely resolved? A. It depends on whether the aircraft weighs more or less than 5700kg. If the aircraft weighs less than 5700kg, then the information to assess safe operation is in the ERSA, as indicated in the What s this? Query in the title. (See Appendix A the end of the article for details). If the aircraft weighs more than 5700kg, then a more comprehensive system is used, which compares ACN to PCN ACN: Aircraft Classification Number is a number indicating the aircraft load on the pavement of specified subgrade strength PCN: Pavement Classification Number is a number representing the bearing pavement strength of the runway (and taxiways/aprons) for unrestricted operation. For aircrew to plan takeoff or landing on a runway, and to taxi on an airport, the aircraft s ACN must be equal to or less than the PCN for that runway and taxiways/aprons, except in
Page 4 emergencies, or when issued an Approved Pavement Concession This system was introduced by ICAO in 1982, replacing a variety of methods then in use. References: 1. AIP AD 1.1-55, 7 Pavement Strength Limitations, incorporating: 2. AIC CO 22/1982 New Pavement Strength Reporting Method. Definitions Mass is the quantity of matter in a body. It is the same everywhere in space. Mass unit: kilogram, kg. Gravity, g: is a force that accelerates a mass downwards. It varies with distance from large space objects, but near the earth is 9.8m/sec 2. Weight is the effect of gravity (g) on a mass (m) =mg. Weight unit Imperial: pound (lb) Oops, Hercules C-130 at Textron s airfield outside Dallas, Texas Weight unit Metric: kilonewton (kn) On or near earth 1kg mass = 2.205pounds weight. Load is Force per unit Area = Mass or Weight/ Footprint. (ACN Load is a dimensionless number) Footprint is the Total Contact Area of the tyres. Deflection is the height difference between a loaded and unloaded tyre. Conversions To convert Into Multiply by pounds weight (lb) Aircraft weight kilograms (kg) 0.4536 kilograms (kg) pounds weight (lb) 2.2046 pounds per square inch kilopascal kilopascals 6.895 pounds per square inch 0.145 In the beginning, aircraft were light, around 400kg, just enough aeroplane to get one or two people into the air. Weak engines and structures of wood, wire and fabric severely limited early aircraft performance. Now, vastly improved small aircraft are still widely used, for private, business, training, charter and aerial work, the aviation equivalent of a car or minibus, but like coaches and semi-trailers, economies of scale favour larger aircraft for payload and range, up to 1000 times heavier than their ancestors! The
Page 5 A380 is the current largest: MTOW 575 tonnes, MLW 394 tonnes, certified for 853 passengers, though max load usually 538 Air France 0neclass, Qantas 484 (14 first, 64 business, 35 premium econ., 371 econ). Crew usually 4 flight and 27 cabin). Early aircraft could fly out of short, grassy fields. The A380 needs a 3km long, high-strength runway. Larger aircraft have advantages. As size grows, surface area grows at the square, but volume grows at the cube, i.e. doubling the size doubles (x2) the surface area, but triples (x3) the volume. There is more room to put things, like people, freight and fuel. That is a distinct advantage, in terms of payload and range. (E.g. The WWII Spitfire, with a small airframe for the engine s power, had low endurance: 45 minutes after takeoff and you are fuel-critical... you need to land, whereas the larger P51 Mustang (same engine) could stay aloft for hours and, with a belly tank or two, escort bombers). Also, larger does not mean more crew. (Though cabin crews usually increase, not so much for more passengers, but to man the extra emergency exits) After the pioneer small plane period, better structures, of aluminium and later, plastic, plus engines of more power and number, permitted larger, heavier aircraft to be built, such as the 1929-built, 66-pax., 56-tonne Dornier DO-X, which had 12 engines (with unfeatherable propellers!). This was a flying boat, as there were then few or no runways long enough to accept this aircraft load. To illustrate the advantage of size, the twinpiston engine DC3 of the 1930s (some are still around) carries 21 pax at 150kt at 10 000ft, through the weather, whereas the Boeing 737 twin-jet airliner, carries 210 pax at 570kt at 35 000ft, flying above most weather. 10 times the pax at 4 times the speed! Both have a flightcrew of 2, which, in terms of pax X speed, gives: DC3: 3,150; B737 119,700, a 38-fold productivity improvement! The WW2 development of Gas Turbine engines has helped power ever-larger, faster aircraft, compared to propeller/piston engines, due to greater power, operating height, simplicity, reliability, smoothness and fuel tolerance, i.e., they ll run on Avgas or Avtur, the latter being a much safer fuel, fire-wise. Numerous WWII Aircraft Carriers were lost after battle damage, due to ignition of leaking Avgas. No modern Aircraft Carrier, with Avtur for its jet aircraft, has been lost. So, bigger, heavier, faster aircraft are here to stay, but they require longer, stronger runway pavements and heavy duty taxiways and aprons. Aircraft tyres This diagram compares three tyres of about the same size,.7m, 27.5 diameter, in terms of: Inflation pressure; Maximum load and Speed limits. Car tyre is designed for continuous use, reaching thermal equilibrium in normal service. Aircraft tyres are designed for intermittent use, with a taxi-time limit but, for their relatively small size and weight, can carry much greater loads to much higher speeds. The Boeing 737 nosewheel tyre in the centre and the F16 fighter mainwheel tyre, right, do not reach thermal equilibrium, due high deflection on the ground. An aircraft tyre, taxied continuously at rated load and 35knots, will continue to heat up until the tyre fails. When an F16, Vref 140kt, touches down, each main tyre is rated for an impact load up to 13.5 times higher than the car tyre s load limit and but 60% of rated speed (SOURCE: Michelin aircraft tyre webpage)
Page 6 The contact points between the aircraft and the pavement/ground is the landing gear wheels, whose rubber tyres contain gas, usually Nitrogen (i.e. air, with oxygen and trace gases removed), as it is inert, so is less likely to add to an overheated-brakes fire and expands less at height. To achieve the performances in the box on the previous page, accurate tyre pressure is essential deflecting on landing (especially heavy landing), steering and running hot during taxi. The high pressure tyre has a small deflection but high load intensity (weight/area), which could be a problem on soft, flexible surfaces (soft subgrade). Under inflated tyres suffer most. Severe overheating from deflection can cause the rubber to revert, or reverse cure. Reverted rubber is like grease with no strength or adhesion to contain the structure, the tyre decomposes, throwing the tread or pieces of it and risking airframe damage. Overinflation (>105%) is also bad, as the tyre footprint is reduced, will wear in the centre of the tread and may explode in use. Inflating the tyre by guess, without a gauge, is the usual cause. Tyre pressures are best checked frequently with an accurate gauge to between 100%-105% of correct pressure e.g. a 30psi tyre should measure cold at 30-31.5psi. (See Aircraft Flight Manual for tyre pressures). Higher airframe weights and speeds need higher tyre pressures, because the tyre is stiffened, better maintaining its shape, improving ground handling and reducing heat build-up from deflection (the difference between the unloaded and loaded tyre section height). Flexing of soft tyre sidewalls during rolling and steering generates a lot of heat and can cause tyres to blow or shed their tread, so 15KT (25kph) is a good straight-line max. taxi speed, for handling and to minimise tyre heat build-up. During taxi, low tyre pressure has a larger footprint (contact area) than high pressure. Tyre/ground contact area is proportional: inversely to pressure and directly to weight and impact. The low tyre pressure spreads the aircraft weight over a greater area, which would be good for taxi on soft surfaces, but bad for impact: This diagram illustrates the effect of tyre pressure on tyre contact area, or footprint. So aircraft tyre operation differs from cars, in that the rolling car tyres continuous ground contact warms it to a thermal equilibrium, but aircraft tyre temperatures are intermittent, changing quickly from cold to hot. E.g.: landing aircraft have cold tyres, from high-altitude cruise in cold air, then rapidly heated on touchdown by firstly, sliding-spinning up to rolling speed and secondly, braking, especially hard braking, heating the tyre further through friction with the runway surface, then taxi, with rolling and steering deflecting the tyre, continues the heating process. Fast taxi on a hot day, after the brief high stress of landing, can blow or deflate tyres.
Page 7 Aircraft Load: Weight per unit area of the aircraft. The force exerted on the pavement. Light aircraft are assessed by using the loading components: weight and tyre pressure. Light aircraft usually impose light loads, so most pavements, including natural ground, can safely support them, providing taxi is on centrelines and care taken on edges, shoulders, which can be weak, as can the off- pavement ground. The black soil plains of Northern NSW are notorious for soft surface after rain. The surface dries, looks hard and firm, but under the crust, is very weak. A horizontal white dumb-bell marker in the signal area below the windsock warns, but may not be present. Some larger aircraft may only impose low loads, due large and/or or numerous soft tyres. The DC 3, for example has ACNs 10% of later RPT aircraft (see table below).military transport aircraft, eg C130 and Caribou can also operate on weak (low PCN) surfaces. That is not the norm, however, as the design aim is to maximise payload: POB, Freight, Fuel, the smallest, highest pressure wheels that will safely support the aircraft on the ground are used, which generally equals high ACN. For aircraft below 5700kg, pavements are rated in terms of: Maximum Gross Aircraft Mass (kg) and tyre pressure, in kilopascals (kpa) and pounds per square inch (PSI). Interpreting ERSA information These are listed in the En Route Supplement Australia (ERSA) for each airport runway. It is assumed that, if the runway is adequate, then so too is the taxiways and aprons. All that is needed is to compare the aircraft mass and tyre pressure to the published data. For example: YSBK s 11/29C runway is listed: 46a 20000/1050 (152PSI), interpreted as: Runway length 4600ft, Asphalt, 20 tonne max GM, max. tyre pressure: 1050kPa (152psi). So, a Piper Cherokee, at around 1510ft (460m) takeoff distance, 1106kg MTOW and 165kPa (24PSI) tyres, is well within the runway limits. If you are operating aircraft below 5700kg, then this technique is all that you need to know. If you d like to know more, or plan to be part of larger aircraft flight crew someday, then read on: For aircraft above 5700kg, ACN/PCN is compared to determine that the aircraft load is equal to or less than the pavement strength. The Aircraft Classification Number (ACN) is based on the same load criteria as for aircraft below 5700kg, but with additions and more detail: Mass kg; Tyre Pressure kpa; Pavement type; Subgrade strength; Pavement loading intensity (i.e., landing gear geometry and area). The resulting ACN is dimensionless. See ACNs in table format on the next page. Pavement Classification Number (PCN) PCNs rate pavements in terms of the aircraft loading that they can safely accept. The PCN is,
Page 8 ACNs for MTOW are listed in table format, as in the ICAO samples below. Graphs can be used to calculate ACNs for smaller mass (see Example 2 on the next page). Aircra& Mass Tyre Pressure Aircra& Classifica2on Number (ACN) kg kpa Flexible pavement Rigid Pavement HIGH LOW HIGH LOW DC 3 11 500 310 5 10 8 9 CitaQon 1 4 380 690 4 5 4 5 B737-800 60 786 690 44 51 51 55 A380-800 431 000 1470 56 75 55 88 ACN EXTRACT FOR A RANGE OF AIRCRAFT Example only, not for operaqonal use Source: ICAO lisqng effectively, the maximum allowable ACN for that pavement. What is a pavement? It is a layer or layers of better quality and stronger material placed and compacted over the prepared natural ground so that no permanent deformation occurs under the design wheel loading. Subgrade The natural surface under the pavement is known as the subgrade, usually soil. This provides the ultimate support for the pavement and the imposed load, so subgrade strength is the determinant of pavement strength. Natural subgrades vary from high to low strength. Aircraft with a high ACN need a high strength pavement, so the subgrade may need to be improved to increase its rating. This can be modified by adding a binder, such as bitumen, concrete or other. Pavement types Flexible pavements comprise a surface bitumen (asphalt) seal coat or layer of bituminous concrete on a layer of crushed rock or gravel on the prepared subgrade. The term unsealed flexible pavement is used where the bituminous surfacing is omitted. Rigid pavements comprise a concrete slab on a crushed rock bed over a prepared subgrade. Flexible and rigid pavements behave quite differently, so are treated separately in ACN-PCN calculation: Flexible pavement loading capacity is calculated by stress carried through to subgrade. Rigid pavement loading capacity is calculated by horizontal stress on the bottom of the concrete slab. Source: FAA PAVEMENT MANUAL
Page 9 Reporting pavement strength Sequence Item/Description A B (rigid). PCN Type of pavement: F (flexible), R C Subgrade strength has four standard categories: Category A B C D Strength High Medium Low Ultra low D Maximum allowable tyre pressure (kpa) E Method by which pavement strength has been calculated experience. Evaluation T U Method Technical evaluation Use. Aircraft Example 1: PCN 40/F/A/1050/T Sequence Item Description A PCN: Pavement Classification Number: 40 B F Flexible pavement C A High strength subgrade D 1050 Maximum Tyre Pressure (kpa) E T Technical evaluation The ACN can then be compared directly with the PCN for corresponding subgrade strengths. Example 2: Graphical solution If ACN exceeds PCN, then the aircraft must not be operated on that runway, unless a Pavement Concession Approval is issued by the airport operator. It may, however, be possible for the aircraft to use that runway at a lower Gross Mass: In the ACN Graph below, the PCN for a runway is 40. At maximum Gross Mass, 80 000kg, the ACN is 42.8 (top line), which exceeds the PCN, so the operation must not take place, unless a Pavement Concession Approval is issued. The PCN can be complied with at a lower Gross Mass. By entering the graph at ACN 40, (bottom line), that indicates that, at 73 500kg Gross Mass, the ACN is compliant. At this Gross Mass and lower, the aircraft can operate unrestricted on that runway. Source AIC CO 22/1982
Page 10 Appendix A: Physical Characteristics Summary An analysis of the Physical Characteristics ERSA information: From left to right: Airport Aircraft Runway Runway Direction 0 M Length/Surface Max # GM/Tyre pressure + Width 11/29C 111 0 *46a 20000/1050 (152PSI) 30/90* Centre/ Magnetic 4600ft/(Asphalt) kg/kpa/ (lbs/sq inch m (Right/ Left) (All RWYS) (The mix of Imperial and Metric units is typical of the ICAO Blue Table of (aviaqon) Dimensions) *46a: = 4,600ft (to nearest 100ft), Asphalt. Other surfaces: b: Concrete, c: Other, e.g. gravel/ grass. (NOTE: Other has a note attached indicating surface material) + Width (metres) Given for two pieces of information: WID: Strip width. Aircraft below 2000kg, min width 10m, advisory min. 15m, typical 30m and 45m. RWS: Runway Surface width, including WID, graded surface either side of the runway (within the gable markers) and ungraded surface, outside the markers. At BK, WID is 30m and RWS is 90m, each runway. At SY, WID is 45m, RWS is 300m, each runway. # GM: Gross Mass, metric equivalent of Weight, pounds.
Page 11 Historical pavement note During WWII, Bankstown was an overall grass field, i.e. Unsealed flexible pavement, so aircraft, even 4-engine B17 bombers, operated on the subgrade. Through the Pacific Islands, many subgrades were weaker than the flood plain soil of BK, so a metal pavement: PSP, or Pierced Steel Planking, was developed in the US. These were laid on prepared sand or coral subgrade, covered by vegetation to improve drainage. The 10ft x 15 (3mx.4m) planks had numerous holes, for drainage, to lighten and stiffen. Planks interlocked and held by clips hammered into place. The US Navy Seabees (Construction Battalion) could clear the jungle with dozers, grade a strip, carpet the ground with local vegetation and then, with a small team of strong men armed with sledgehammers and a large quantity of PSP, build an airfield within 3 days, with a 3000ft x 200ft (914m x 60m) runway, ready to go. Allegedly, a heavy-landing fighter could bounce 30ft (10m) into the air and heavy bombers made waves across the PSP. By Bill Cooper Pierced Steel Planking (PSP)
Page 12 Planes That Flopped The X Files Hafner Rotabuggy Photo: Middle Wallop Army Museum File X128 To fight a war you need a lot of resources, not just personnel but material as well. If the battle is nearby, then you do not need to carry too far the weaponry needed, but if the fighting is some distance away, then the logistics of transport can be problematic. As opposed to the battles of the distant past where artillery pieces had to be dragged overland, generally by horse and carriage, in the battles of the recent past and of our modern times, air transport by heavy lift aircraft was and is utilised. Building aircraft dedicated to this task is expensive but what if the material you need to fight a war can fly itself to the front? This question was given serious thought due to successes in early rotorcraft development. Raoul Hafner was born in Austria and had been experimenting with rotorcraft in the mid-1920s. Taking one of his experimental aircraft with him to use as a test rig, in 1932 he moved to England where he learned to fly Cierva gyroplanes. From what he learned, he built his own autogyro which he called the A.R.III. This aircraft first flew at Heston Middlesex in 1935. It was similar in many respects to the Ciervas that he had been flying but its rotor head control system was significantly different having both cyclic and collective blade pitch control, a feature now standard on helicopters. In the late 1930s, the Air Ministry issues specifications for rotary wing aircraft to be used in the fleet shadowing and convoy protection roll. Hafner contributed proposals to the specification based on his autogyros. Nothing really came of these as with the outbreak of war, Raoul was interned as an enemy alien. After a little while in the following year, he was released and was able to pick up where he had left off with his work. He began working for the Central Landing Establishment at Ringway in Manchester under the auspices of the Ministry of Aircraft Production on a man-carrying machine called the Rotorchute. Silk for parachutes was in short supply and it was thought that rotary wings for individual soldiers might make parachutes in a lot of applications redundant. After some initial failures, the concept was proved to be sound. With the eventual successful testing of the Rotorchute, Specification 10/42 was issued for the idea to be developed into something that can be utilised on military vehicles as this concept proved to be financially cheaper ( 343 as opposed to 2,470 for a Horsa vehicle carrying glider) and simpler than building aircraft dedicated to the task of carrying military vehicles into battle and besides, it could land in a more confined space. The idea was to glide the vehicle onto the battle field after it had been towed there, land, shed the tail unit and rotor and then be used as the vehicle was intended, that is, a ground based vehicle. The Willys 4 x 4 jeep was
Page 13 Photo: Nevington War Museum chosen for the experiments and it was designated Rotabuggy or perhaps less imaginatively, Flying Jeep. The first thing to do was to find out if the jeep could withstand the rigors of landing. To do this, a jeep was loaded up to simulate the weight it would carry with people aboard, winched up to about 8 feet, given a swing motion to simulate contact with the ground from an approach and then dropped onto a concrete floor. This was done seven times just to be sure and the Willys proved to be a tough nut as no damage was sustained to the vehicle, its tyres and wheels. So far so go. Now that it was proved that the Willys Jeep was up to the job, the next thing was the rotor, tail unit and to do something with that nonaerodynamic windscreen. The rotor that was developed was just short of 49 ft in diameter and was wooden in its construction with stainless steel root attach fittings and the blades had a slight in-built twist to ensure that they operated at their optimum angle of attack. The tail unit was of a monocoque plywood construction twin fin arrangement that had 4 attach points to the rear of the jeep. There was also the provision of a tailskid that served 2 purposes, firstly it was designed to alleviate the potential of rotor strike of the ground on landing and secondly, it had a pulley on the end to act as a pre-rotator cable guide so that the cable did not foul up with the fuselage as it was drawn by the ground vehicle to get the rotor spinning. Careful consideration of the structures was required as the rotor and tail had to be hardy enough to withstand flight and landing loads but also be simple enough so that these units could be quickly shed upon landing to make the vehicle ground usable in the shortest possible time. As for the windscreen, it was replaced with Perspex sheets surrounded by a metal frame that was much more streamline in shape and the cockpit/cabin was now fully enclosed. Along with the regular instruments needed to drive along the ground, some flight instruments were required and these were added to the dashboard on the starboard side. The pilots of the jeep were able to communicate with the tow pilot via a telephone cable that ran along the towrope. The rotor was a scaled up version of the type used on the Rotorchute and was fitted on a pylon above the front seats. The rotor hub was kept as close as possible to the roof of the jeep for landing stability purposes. To reduce vibration
Page 14 forces transmitted to the pilot, the pylon had an unconventional elastic suspension. To get the rotor spinning, a 150 ft cable was wound 74 times around the hub capstan and pulled by a ground vehicle just prior to launching and the forward motion of being towed sustained the rotation. The Rotabuggy had been assembled in Slough and on 28 October 1943, it was taken by road to the Airborne Forces Experimental establishment in Sherburn-in-Elmet for testing. On 16 November, ground runs commenced by the Rotabuggy being towed behind a truck, the speed of the truck was insufficient to get it airborne. The tow hitch was the standard glider type of the time, the Malcolm Mk 6A, mounted above the reinforced bumper. The pilot had a standard glider release handle when he was ready to let go of the tow plane or in the case so far, the tow vehicle. The truck proved somewhat deficient in the speed stakes and some more serious grunt was needed so on November 24 a supercharged 4.5 litre Bentley was purchased in London for the towing task. Three days later, the Bentley managed to tow the Rotabuggy fast enough to get it into the air and then back down again as it decelerated. The Rotabuggy became airborne at 60 km/h with 235 rpm on the rotor; no stick vibrations were evident with this test. The Bentley then gave way to an Armstrong Whitworth A.W.38 Whitley V bomber on 9 December 1943 having been retired from active service a little over a year before due to its obsolescence. Experiments were conducted towing the Rotabuggy at various speeds and this time stick vibrations became apparent especially at 81 km/h where now controllability was being affected. The Bentley took over towing duties again until the issue could be sorted that resulted in a minor mishap where the rotor made contact with the tail. After repairs the Whitley took over towing again on 30 January 1944. Testing revealed that a maximum speed of 112 km/h was all that the aircraft could withstand. A more serious accident later occurred when being Bentley towed where the jeep swung through 170º on landing with both blades striking the ground. It was March by the time testing resumed. Vibration was still a problem and various means were tried to solve this issue. Landing proved rather tricky as this was done while under tow. Various things were tried including releasing the cable just prior to touchdown, after a while it was found the best technique was to slowly bring the Rotabuggy near the ground, releasing the cable and let it run on without moving the stick forward while it ran along the ground. One curious feature that was discovered during testing that a pilot does not normally have to think about is the position of the front wheels. It was found that if the front wheels were not straight, the Rotabuggy would yaw in flight. To assist the pilot in this regard, the steering wheel was elasticised to neutral and a mark on the wheel indicated where the neutral
Page 15 position was so that on landing, the jeep would not go spearing off one way or the other. As a part of the original specification, the aircraft had to be able to be flown by a normal RAF pilot, it should not be complicated to fly and that only a short conversion course would be needed. To comply with this stipulation in the specification, the rotor control system that had been on the Rotorchute and was now to be applied on the Rotabuggy was modified by the addition of a linkage so that the flight controls acted in the correct sense. While great care was taken to ensure that the Rotabuggy s flight control system was as standard as possible, there was one thing that was unable to be achieve in the prototype and that was the ability to fly it solo. All testing had to be done with two aboard as a single pilot alone could not reach and handle all the controls for this most unconventional machine. thoroughly exhausted he almost fainted when it was all over. For all intents an purposes, this sealed the fate of the Rotabuggy as there was now no real need for this kind of craft as the D- Day landings had taken place with the transportation of jeeps in Horsa and Hamilcar gliders proving to be practical and jeeps proved to be able to withstand the rigors of a parachute drop after being pushed out of aircraft. As could be seen, there were a lot of problems to overcome to make such an idea work. Simultaneously while the problem(s) solving was taking place, plans were underway to look at applying this solution to a tank! The idea did not get too far as there was no one tug able to haul a 15,875 kg (the weight of a Valentine tank) hulking piece of machinery into the air, in fact it was proposed that a Halifax tow the tank with a Dakota towing both of them! While this concept ultimately lead to a dead end with the Rotabuggy being struck off charge on 1 December 1947 and then reduced to scrap, the R and D that Hafner put into this project proved invaluable for post-war British helicopter development for the Bristol and Westland companies. Photo: Nevington War Museum On 11 September 1944, the Rotabuggy was now finally ready for free flight testing. Squadron Leader I. Little was to act as pilot with Flight Lieutenant R. Packman to act as driver. The plan was to be towed to 7,000 feet, release, and then free glide back. The attempt was aborted on climb out at 1,500 feet when a severe rotor vibration developed that called for all the pilot s strength to maintain control. Little asked the pilot of the Whitley tug to slow down as much as possible and circle round for a landing. The Whitley flew at just above stall speed with Little fighting for control all the way. A successful landing was made but with Little now Acknowledgments British Prototype Aircraft, Ray Sturtivant The Illustrated Encyclopedia of Aircraft, Orbis publication Aeroplane Monthly, October 1991, IPC Magazines By Anthony Coleiro
Page 16 RPL to PPL (Part 6) Class Charlie Attempt #2 So far, my odyssey to PPL has taken me from dual Navs to first solo Nav to an unsuccessful Class Charlie (CTA/controlled airspace) attempt. It's now time to complete my second solo Nav. I arrive early at the club prepared for a round trip to the Hunter, with stops at Warnervale and Cessnock. Instructor Isaac checks my logbook and informs me that since I haven't flown for over two weeks I must do a dual session before I can fly a solo Nav. This is disappointing, as it is a nice day and the weather all spring has been terrible. Unfortunately, no instructor is available this day to do a dual with me, so Isaac books me in for the next morning with Andrea. The plan is to do a CTA departure to the South followed by Victor One North and a Harbour Scenic. This will fulfil the Class Charlie controlled airspace requirements I didn't achieve on our aborted Canberra trip. Andrea suggests I prepare two plans, one for a CTA departure via Picnic Point and Sutherland, and the other a normal Class G departure via Camden, Appin and the Seacliff Bridge near Wollongong. I submit the CTA flight plan to NAIPS, and we prepare to depart in SFK, with a low ceiling of 2500'. We request an airways clearance on startup and are advised to proceed to the Charlie runup bay for runway 11C, as the more commonly used 11L is unavailable. Ground advises that if available, the clearance will be issued in the runup bay. Isaac books me in for the next morning with Andrea An ATC departure requires great accuracy in navigation, and I don't as yet trust my mapreading skills for this level of precision. In the bay I launch OzRunways on my ipad, which will allow me to track the route easily. At this point, Murphy strikes and the ship icon has disappeared from the OzRunways map! Andrea says no problem we ll use the Garmin 430 in the panel. At the runup bay ground advises that the CTA departure is not available. OK, so we change to plan B and depart downwind to Camden.
Page 17 I esqmate our arrival at the Sea Cliff Bridge, and suddenly we are on top of it bang on Qme I forget to write down the takeoff time, so estimate and log it somewhere over the railway line on the boundary. I elect to use the maps now rather than the 430, and after a bit of waffling around between Bringelly and Mayfield, due to momentary uncertainty of my position (not lost...) Andrea says why not just use the headings I had already worked out? So I point south and there is Camden airport in front of us. I call Camden inbound to overfly the airport and am informed that there is no reported traffic, Andrea correcting me that my call to Camden should be overfly, rather than inbound. On track and on time Appin appears dead ahead. However, I have been so busy concentrating on finding Appin that I fail to notice Wedderburn airport until suddenly I see it just out there off the left wingtip. As we turn East to track towards the coast I belatedly tune to the Wedderburn CTAF and inform them of our passing. Coming up to the coast, and it s a bit bumpy sandwiched in between clouds at 2500' and the 1000' elevation terrain at the escarpment. I ve had worse. I estimate our arrival at the Sea Cliff Bridge, and suddenly we are on top of it bang on time. I had not seen it creep up as it was right under the nose, so, note to self, next time plan to fly a bit to the right of such landmarks to allow for easier identification. Out over the water we descend to 1000' AMSL and suddenly all is smoothness, peace and serenity. Turning north I gaze at the spectacular Sea Cliff Bridge on my left and ahead to Stanwell Park beach. Switching the fuel pump on I remember that I had planned a fuel tank change at this point about 30 min from Bankstown, but then wonder aloud whether this is a good idea over the water. I suggest to Andrea that maybe we do it now anyway because Stanwell Park beach is close by in case the tank change creates a problem, and she agrees. I decide next time I'll plan the change at Appin, near Wedderburn. I sometimes find cross-country flying is hard work, as so much is not yet second nature to me. I m optimistic that this will diminish with practice; but right now, I am entranced with the sheer beauty of the situation, the smoothness of the air, the majesty of the bridge, the view of the cliffs and beaches as we look in from over the sea.
Page 18 A rugged and beauqful coastline With landing lights on we proceed north on Victor One, and make our presence known on the Victor One CTAF 120.8. Approaching Jibbon Point we descend to 500ft and this is truly magic! A well-trimmed SFK is quite happy and stable at this level, and there is little sensation of speed over the ocean despite our low altitude. I have been on Victor One before as a passenger, and about 10 years ago as a very part-time student, but this is the first time I have flown this route seriously in training. The Sydney flying community is indeed privileged to have this spectacular route available in Class G uncontrolled airspace. There is no traffic in or out of Sydney airport at the moment, and passing Botany Bay I see the two North-South runways reaching out to us. Although they seem to be not far, Kurnell would be a better option if things went quiet up front! On the CTAF comes a report from SXF heading out from the Parramatta River. I know this aircraft, a Cessna Caravan from Sydney Seaplanes. I live on the Parramatta River, and each day see and hear the Caravans and Beavers weaving their way to and from their work at Rose Bay flying 500ft above the water. I have occasionally seen one in the runup bay around 9.30 am while preparing to depart on a Nav. Today I watch the Caravan slide into view just above the horizon, and enjoy this feeling of brief brother/sisterhood. Kurnell to Botany Bay We commence our climb to be at 1500ft by Long Reef, and I request Class Charlie airways clearance for a harbour scenic. Sydney comes back with a negative. Andrea tries again, but no luck. I say do we just call it a day and head to Hornsby and the lane of entry. Andrea suggests we should at least fly up to Brooklyn Bridge and try for a Class Charlie clearance via Richmond great idea! We cruise north over Broken Bay with
Page 19 Barrenjoey to our right and the wakes of miniature Berowra boats to our left. Andrea shows me how to set Direct To on the Garmin 430, and there is our course to Richmond. I have played about with the 430 on the ground, and watched instructors use it in the air, but have never really used it much myself as yet. So we fly to Brooklyn, and I notice the magenta line sinking to the left. When I point this out to Andrea she simply hits the Direct To button again, and bingo, of course the course originates from our current position! There is nothing like a real life demo to turn theory into practice. We reach Brooklyn and I contact Richmond for an airways clearance, but again no luck. Well that's OK, we have had a wonderful time, and we turn south towards Berowra. Over Pennant Hills the ATIS tells us that 11C is still in use. I call inbound at Prospect and am told to report established at 3 miles, which is Warwick Farm. So I gently turn towards the Velodrome. Andrea says I think we re a bit far to the left muscle memory has put me on a track for downwind 29R. It has been more than a year since I last used the 11 direction and my personal automatic pilot has over-ridden my conscious brain; plenty of time to correct however, and I manage a passable landing. I do enjoy the straight-in BeauQful Bondi approach from Prospect, and I wish the 11 direction would be used more often. I stop SFK in the gap between 11C and 11L, and wait for a clearance to cross 11L. Andrea says they will know we are there, but after a minute or two I transmit a subtle reminder and we are cleared to cross 11L, then back to Schoies. Well we didn t get the CTA departure or the Class Charlie controlled airspace requirements, but for me this training session is an end in itself. In fact they all are, rather than simply boxes to be ticked en route to a PPL. I thoroughly enjoy each one, and learn much that is new every time. During the debrief I comment to Andrea about the amount of info that must be assimilated and acted upon, but she assures me that it s probably because of the sporadic nature of my sessions, mainly due to many weather-related cancellations. That s fine with me, because I m pretty much on target, and if there are some make-up hours to be flown, then flying is flying! I will get those Harbour Scenic/Class Charlie and CTA boxes ticked, and have a lot of fun doing so. PS Murphy s ipad ship icon disappearance was due to Location Access being switched off in Settings By Justin McCoy
Page 20 Instructor s Patch The Taboo around the Flight Review First off let me start off by saying what a fantastic environment SFC is to work in and be affiliated with. I have now been with the Club as the Multi-Engine and IFR team leader for a little over a year and have loved every minute of it. It is great to see such a diverse group of pilots flying for both leisure and a career under the one roof. It is fantastic to see the hustle and bustle with 25 plus full-time students during the week and a growing number of private members on the weekend. When I first started, the weekends were relatively quiet. Having worked nearly every Sunday for the last year, it is amazing to see how much the club atmosphere has been fostered through competitions, Breakfast with Victor, and fly away events. Kudos to all of the behind the scenes work that David Jaffray, George Higgins and others on the social committee have been able to accomplish. The turnout for the recent Breakfast with Victor was incredible compared to a year ago. I am a big supporter of flying for recreation as well as a career choice. It is not unusual for me to fly the occasional Harbour Scenic/Victor One or Angel Flight every few months just to get out and enjoy the miracle of flight. However, in order to do so, we all have to pass that dreaded flight review. Over the years, I and other instructors have conducted a good many flight reviews for both single engine and multi-engine class of aircraft. It is a common misconception that this is purely an assessment and an instructor is not allowed to render any assistance at all. This is not at all the case. The CASA factsheet on flight reviews actually states that a flight review should include training, and an assessment. Training is included to bring you back up to the required standard of competency, if you need it. Yes, it is true that an assessment has to be made at the end of the flight, but there are no restrictions on us showing you handy tips and tricks of the trade to improve your skills. Every flight review I conduct, I make a habit of ensuring that the reviewed pilot comes out having learnt something new. Of late the three of my biggest concerns are starting aircraft techniques, ground operations at YSBK, especially around the clubhouse and hangar, and finally radio calls. I make a habit of ensuring that the reviewed pilot comes out having learnt something new. Instructors quite often notice that pilots who only fly a handful of hours a year are extremely nervous before the finger clicks the feared PTT
Page 21 button to talk to ATC. SFC has published a complete set of radio calls that we generally use with student beginners but we are more than happy for private club members to ask for a printout from the front desk. This printout covers everything from operations in and out of Bankstown as well as a lot of handy calls for CTAF operations etc. If it s been a while between flights or you want a refresher, get a copy. To me a flight review is just as much a learning exercise as it is an assessment. I like to see you in your element, how you normally operate. When I embark on a flight review, even during the pre-flight planning stage, I don t want to see anything other than what you usually do. For example, if you use AvPlan or OzRunways on ipad in-flight, I am more than happy for you to do so on a flight review. I have a lot of experience with AvPlan (for OzRunways, see our resident expert Dave Winter) and would prefer you to ask questions about its functionalities rather than hide it for a flight review, just to go back to using it next time by yourself. or decide to renew their licence for another two years, we will need to conduct more and more flight reviews. It is my goal to have the instructor team create a supportive environment in which we are approachable and to eliminate the taboo around flight reviews. When it s your turn to come up to us for the dreaded flight review, I would like you to be able to relax and look forward to it as an opportunity to learn some new concepts, have questions answered and brush up those elements of your flying that have become a bit rusty. By Mitchell Anderson 2017 PRIVATE HIRE (incl GST) TYPE VH HIRE LND I like to see you in your element, how you normally operate if you use AvPlan or OzRunways on ipad in-flight, I am more than happy for you to do so on a flight review. Having said that though, please make sure that if you are using an Electronic Flight Bag (EFB) that it conforms to the CASA CAAP 233-1 and always have a backup, be it a second ipad/iphone or current paper charts, handy. Don t think that the instructor sitting next to you is there to intentionally pick faults or try and fail you. In fact, most instructors enjoy conducting flight reviews, as it gives as a nice change of pace from the full-time training environment which occupies a large portion of our flight time. We are there just as much as the social committee to foster the club environment, improve flying standards and most of all enjoy flying. As more and more members join the club Tomahawk CNV $159 $19 Warrior II FTU IJK EOM INB $209 $22 Warrior II SFM $219 $22 Warrior III SFK $229 $22 Warrior III ZFX ZFY $239 $22 Archer II NBF SFA $249 $23 Archer III SFR $259 $23 Arrow III SFJ $289 $27 Cherokee 6 CDK $319 $32 Cessna 206 LZN $399 $33 Cessna 206 AZN $419 $33 Duchess WZA $409 $37 Red Bird FS FMX $99 N/A For full details www.sfcaero.com.au/aircraft-rates
Page! 22 Cones of Sadness I learned about taxying from that A beautiful day at Bankstown and I'm ready to do my twice delayed second solo nav which involves two destinations. Today I have prepared three options; Mittagong and Goulburn, Mittagong and Wollongong, Warnervale and Cessnock. Fog in the south means that The Hunter is the preferred route today. I move forward a couple of metres with the sun in my eyes I know what has happened, I have taxied into some cones. Back to the club and I report my crime to Andrea. She rings maintenance and they come down with a tug. The prop appears to be OK, as the cones are fairly soft fibreglass, but the LAME says he will have to check the paperwork to find the relevant procedure to be followed after a prop strike to a cone. and there is a sickening crunch. My aircraft is SFK. According to the maintenance release it is in need of a tweak to the Artificial Horizon (AH) which is reading 5 degrees down on the left. Andrea at the desk makes a phone call to the maintenance centre and they say it will be a quick fix, so I agree to taxi it up there myself. Out at the aircraft I call for full fuel. The fuel truck will be a little while so I commence preflighting while waiting. After the fuel truck departs I am already in the cockpit and go through the start checklist, fire up, and prepare to taxi to maintenance. I move forward a couple of metres with the sun in my eyes and there is a sickening crunch. I straightaway pull the mixture back and the engine stops. In the sudden silence I complete an incident report, and decide not to take up the offer of hiring another aircraft for the
Page 23 solo flight. Sometimes you have to quit while you're ahead. Why did this happen? I have analysed the situation, and like any incident involving an aircraft there is a preceding series of events, one of which in particular if changed could well have prevented the misfortune. My personal preflight checklist ends with "stand back and check the aircraft from the front". I didn't do this for two reasons: I was only taxiing not flying, and I was already in the aircraft having waited for the fuel truck. My intention was to do a fuel drain and complete the preflight after the AH had been adjusted up at maintenance. Had I completed the checklist including the "stand back..." check I would have seen those cones. The sun straight ahead was the final piece of the jigsaw, as I had assumed the grass in front was clear. "Assume makes as ass out of u and me" comes into play here. The lessons learned for me are that there is never a reason to omit items on the checklist just because a non-standard procedure is taking place, or a familiar pattern is interrupted, but more fundamentally never to taxi an aeroplane unless I can clearly see what is in front of me. The following day I de-brief with Safety Officer Paul Blackshaw. The intention of this interview is to explore any issues that may have led to the incident and to establish the whys and lessons learned, while not apportioning blame. Paul asks me some pertinent questions to do with my activities leading up to the event, eg, was I fed and watered (I was), any alcohol the night before (no), had I spent much time preparing for the flight (three flight plans spread over a couple of days, so yes) and slept well the night before (not too bad). We then move on to the day itself: any undue anxiety (not really, a nice day, familiar aircraft, well planned flight, although for me any solo flight, especially cross-country, is an extreme adventure), any time pressures (no), good sunglasses (yes, polarising), any other contributing factors (none that I could think of). These focus on always treating an aeroplane as a creature with the ability to bite Paul lets me self-debrief and then offers some constructive insights. These focus on always treating an aeroplane as a creature with the ability to bite, regardless of whether it is about to start up, taxi or fly. He points out that an Undesired Aircraft State can potentially exist in any of these situations. I offer that at this stage of my flying I have not yet acquired the experience to dispense with
Page 24 checklists for almost all the necessary sequences. We discuss the analogy of a P-Plater vs a more experienced driver; whereas the novice might have to consciously remember every aspect of a manoeuvre when say, changing from outside to middle lane, to the veteran the sequence of checking internal and external mirrors, turning head to check blind spot then allowing for another car to potentially merge into the intended lane from the inside is all second nature...i hope so anyway. I imagine that with time I might acquire this second nature ability, but for now checklists are the go, for everything. Paul explains that checklists for airline pilots are purposely kept brief so that if there is an interruption, the pilot can easily go back to the beginning, thereby making sure nothing is missed. I mention to Paul that I have written down what happened with a view to submitting a newsletter article. He thinks it could be a good idea but reminds me that I will be outing myself as the perpetrator! Having read many I Learned About Flying From That and Aftermath and MacArthur Job Aircrash Investigations articles and stories over the years I'm OK with that. Paul advises me to: 1) not be too hard on myself as it can happen to anyone; and 2) not to wait too long before getting back on the horse. My work commitments mean that it will be a couple of weeks before I can remount, but hopefully SFK will forgive me for the indignity I have put her through and we will complete that solo flight. By Justin McCoy SFC Merchandise Cap $20 4GB USB Card $10 Water bottle $5 Shoulder bag $5 Pen $2 Give flying for For special occasions with a Sydney Flying Club: Taster Training Flight $150 Warragamba Training Flight $180 Nthn Beaches Training Flight $270 Three Sisters Training Flight $310 Harbour Scenic Training Flight $340 Sydney Coastal Training Flight $380 Flt Training Experience Pack $1350 As a PS, I noted that the two LAMES who came down in the tug to minister to SFK independently looked through the left and right cockpit windows before touching the prop. They were checking that the keys were out of the ignition. These experienced gentlemen take nothing for granted, and as a result maintain a full complement of arms and legs. Purchase over the phone, receive voucher by email 02 9709 8488
Page 25 Safety Column An Airmanship Refresher? Hello again everybody another instalment of our Safety Column from the Safety Department. This also marks my last as the Safety Manager, as I have made the decision to relinquish the role in order to spend more time with family. It is timely to re-examine some issues that have occurred during my time in the role. As I have said on numerous occasions in answer to the question "What are the issues that I should be aware of? Airmanship is the answer. Almost always, this is not the answer that the questioner wants to hear. It is also in danger of being viewed as too simplistic an answer. It is very much a feature of our "human-ness" that we want an answer that we can use in a simple way to help us fly more safely. It is a good thing that we, as a group almost as one, striving to do "the right thing". Not just for the sake of it, but for the obvious reason that we all want to get home safely. I have embarked on an exercise to elevate the subject of Airmanship in the hope that its lessons can be used to make our flying activities safer and at the same time simpler and more enjoyable. A more relaxed pilot, one who has employed the "Five Ps" (Prior Preparation Prevents Poor Performance, and by the way, some people use 6 P's!), is not only going to return with a bigger smile, they are going to return...full stop! And, this pilot is more likely to make this
Page 26 return without having to fill in an Incident Report, or having to have a talk with the HoO/ CFI or the Tower! So, what are the issues that we need to talk about? We have had one instance of an Engine Fire on Start. In this case it was determined that no mechanical deficiencies existed. We couldn't determine if pilot action caused too much fuel to pool below the carburettor, but it is highly likely. It only takes a small back-fire to ignite this fuel. An understanding of the POH (Pilot's Operating Handbook) will give insight as to why this has occurred and the steps needed to overcome the situation. If one revises the Kern Airmanship model, they will see that Knowledge is a very important structural component of the framework that pilots use to conduct themselves. I know that I am in danger of becoming repetitive, or a nagger, but I really do mean to stay on this path to be helpful! Discipline is also the foundation or bedrock of the model. In simple terms it means having the discipline to read the manual and not rely on old wives tales. So, in our Engine Fire on Start case, we will see that crucial information can be found in the POH, but one has to look for it. The manufacturers and the regulators will not spoon feed us, they will simply present information for the trained crew member. That is to say that they will only include information that is not obvious given our previous training. Sections 4 and 7 of a POH are very important but no more important than any other chapter. In simple terms it means having the discipline to read the manual and not rely on old wives tales. Another issue that raises its head frequently is that of the Airspace Incursion or AI. This means an entry into controlled or restricted airspace without the pilot receiving a clearance from ATC (Air Traffic Control). The airspace around the Sydney Basin is rather complex and cannot be treated lightly. There are many web-based resources that can be viewed before one ventures out for a fly. As I often say: "Be curious and make Google your friend." Use the online Visual Flight Rules Guide (VFRG), On Track and all the other information that CASA makes available. There are also videos that CASA publishes via YouTube. One can even go further and use Skybrary, the online resource published by Euro ATC, and the excellent FAA library. Yes, this does mean that you will spend extra time preparing your flight but you will protect yourself and that of others. Just consider some of the possible worst case scenarios of an AI e.g. the controller who becomes distracted by unidentified traffic approaching their airspace and forgets to provide a heading change to an aircraft in controlled airspace. The ramifications are too terrible to describe. Another example is the aircraft that strays into Restricted Airspace, just as a live firing exercise commences. It may also surprise readers to learn that foreign airline pilots may not be aware of the airspace structure around major airports other than to fly the departure gradient as charted. This is often presented as gradient in percentage only and not a requirement to reach a height by a particular distance. This is particularly pertinent when heavier jets are departing to the north from Sydney. In fact, in some countries there is no such thing as uncontrolled airspace, so these pilots will have a differing perception of the threats that are present during departure. In this case, a heavy jet may be only 500 feet above the control area step.
Page 27 All tools at one's disposal are required to make it simple to keep clear of airspace that shouldn't be entered without a clearance. Use the websites that I talked about earlier. Study the route to be flown, even if it's only a local flight and "I'm not going far.. Find additional strategies that will keep you from making a huge mistake. Use additional lateral tolerances even though the rules don't specifically require it. Pretty good TEM (Threat and Error Management) in my opinion. And for that matter, use a vertical tolerance or buffer as well. If one flies at the same height as the step, then any error in altitude keeping may well result in an AI. What navigation tools do we use? Do we use the GPS that is installed in the aircraft to its full potential? Do we know how to use some of the GPS features to provide a DME distance when the aircraft is not equipped with one to back up our visual navigation with a sensible tool. One trap that catches the unwary, is direct tracking using a GPS. Unless you are absolutely, positively sure that you won't penetrate Controlled OR Restricted Airspace, then don't do it. Another great tool is an EFB or Electronic Flight Bag. When used as a labour saving device, it is worth its weight in gold. Just make sure that you know how to use the particular device and the application before you use it in anger. We have had situations where lack of familiarity with the device has caught the pilot out at the worst possible moment. Read the CASA CAAP on EFB use in flight beforehand as well. Do keep in mind that the CAAP is written for AOC (Air Operators Certificate) users, so for us it is a good guide. In the Kern Airmanship model, you will note the pillar of knowledge of Team. Readers of my earlier articles may recall that I have mentioned armchair flying. If you are using videos and pictures that CASA provide via YouTube and On Track, find a quiet place to visualise the flight and rehearse flight progress in manageable chunks. Try your best to accurately picture the features that you have chosen earlier to prevent an incursion. This will be a great way to employ the old adage of "Don't put your aircraft anywhere your brain hasn't already been". "Don't put your aircraft anywhere your brain hasn't already been. Why would I be bringing this up now? Some of our AIs have occurred partly because the Pilot in Command (PIC) has been trying hard to enhance the experience for their passengers. This is a workload and a distractor that will be very unfamiliar to a lot of us. If we consider this in a TEM light, then we should consider introducing even greater buffers if we are carrying passengers and are in effect conducting a joy flight. That question, comment or other distraction, I will assure you, will come at the best time for Murphy to catch you out. Consider how to brief your passengers about how to conduct themselves and when to talk to you. For example, airlines impose a procedure called the sterile cockpit, whereby only operational conversation is permitted at critical phases of flight. A couple of instances of landing with feet on the brakes or too early or exuberant braking have