Enav perspective of RWY Incursion Hazards and Proposed Mitigation Strategies associated with aerodrome design ISTANBUL, 5/8 November 2013
Getting to the roots of the problem
Most of the main European airports date back their foundations from the pre-war to the early 1960 period. The inherited aerodrome design is not meeting the high traffic volume operational & environmental needs. Cities have often surrounded the airport fences. Sudden and not always well controlled grow of the airport infrastructures,... hence... TWR line of sight frequently limited
Human factor Complex or inadequate Aerodrome Design ICAO Doc 9870
COMPLEX OR INADEQUATE aerodrome design significantly increases the probability of a runway incursion. The FREQUENCY OF RUNWAY INCURSIONS has been shown in many studies to be related to the number of runway crossings and the characteristics of the aerodrome layout. POOR INFRASTRUCTURE DESIGN has highly contributed to the quantity and severity of runway incursions. All studies confirm the relevant role of an appropriate aerodrome layout in managing runway safety. Airfield design is a process that must balance safety, efficiency, capacity and enviroment TAXIWAY AND AIRFIELD DESIGN PLANNING GOES HAND-IN-HAND WITH OPERATIONAL CONSIDERATION
AN IMPORTANT FACTOR IN PREVENTING RUNWAY INCURSIONS IS TO LIMIT THE PHYSICAL POSSIBILITIES FOR PILOTS AND VEHICLE DRIVERS TO MISTAKENLY ENTER RUNWAYS. This basic principle includes, but is not limited to: The simplicity and logic of taxi/runway lay-out. The avoidance of runway crossings The optimal use of perimeter taxiways for a/c The compulsory use of segregated service road for vehicles The avoidance of using a runway as a taxiway...
OPTIMIZE PILOTS RECOGNITION OF RUNWAYs TO INCREASE SITUATIONAL AWARENESS AND ENSURE THAT TAXIWAYS LAYOUTS TAKE OPERATIONAL REQUIREMENTS AND REALITIES INTO ACCOUNT: FULL PARALLEL TAXIWAYS limit direct and unaware entries onto runways and provide easy access to each runway end Use a RIGHT ANGLE FOR TAXIWAY conducting to the runway (except high speed exit) AVOID WIDE EXPANSES OF PAVEMENT AT RUNWAY ENTRY (VERY WIDE TAXIWAY) HF problem: the ability, to see and understand the holding points, is compromised Avoid maintaining THE SAME NAME TO A TWY making several turns along its route Limit the NUMBER OF TAXIWAYS INTERSECTING AT ONE SPOT Implement STANDARD TAXI ROUTE Implement, whenever possible, ONE WAY TAXIWAYS Highly consider the opportunity to modify the taxiway nomenclature to maintain it INSTINCTIVE
What can be done and how ATC can help. Runway crossing Pilot expectations
Use strategies to reduce the number/severity of active runway crossing: PROMOTE THE BUILDING AND USE OF LOOP PERIMETER TAXIWAYS TO AVOID RUNWAY CROSSINGS OR AT LEAST: Ensure proper TRAFFIC FLOW STRATEGIES KEEPING THE CROSSING POINT AT THE LAST TWO THIRDS OF THE RUNWAY, the risk of category A or B incursions is higher for crossing occurring in the first third of the runway, USE ONLY RIGHT-ANGLE TAXIWAYS, never use an high speed exit for entering the runway ( aircraft and vehicles); Must issue a specific clearance to cross any runway, Avoid to insert the crossing clearance inside a complex/long message or taxi instruction Avoid the contemporary use of conditional clearances
New configuration at the end of 1998 Increased volume of traffic since then Rwy incursion connected with the crossing 35L : 18 ( 2004-2009) NEW TWY H BUILT (2007/09) TWY H length 2,5 KM Useful when 35R is used for departure Useless when RWY 35R is used for arrivals (due to noise abatement runway configuration changes every 24 hours) Compulsory use of 35R for departure in LVP and consequently of TWY H. Runway incursion, connected with the crossing, after the TWY H opening to today :
The role of expectations
These unusual location for the RHP are frequently missed by pilots and leads to R.I severity type D Due to OFZ requirements or displaced threshold PILOT EXPECTATION
As the airport reopened to traffic after a renovation, the number of runway incursions showed a problem which couldn t be ignored. It was clear since the beginning, the main trouble was related to RHP on TWY A followed by RHP K1, that it was involved in less than 1/4 of the total incursions ACTION TAKEN: LRST in action! An HOT SPOTS map was published in AIP (first time in Italy) and reproduced on the first page of each PIB/meteo folder given to pilots (periodically repeated) ATCOs and airside operators have been trained & stressed on the subject. The situation is constantly monitored, analyzed and data up-dated.
60 50 40 30 20 10 0 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 Incursions on RHP A
ACTION TAKEN: Hotspot map, but wasn t enough hence Increase pilot awareness introducing the use of ad hoc fraseology TWR: I-ALDE TAXI TO CATEGORY III HOLDING POINT G RUNWAY 29 Huge reduction of misunderstandings, hence of R.I.
Data on Enav airports
80 70 60 50 40 30 20 10 0 2010 70 29 1 1 1 A B C D E n.c. NO ATM ATM 35 30 25 20 15 10 5 0 2011 31 17 19 2 1 1 A B C D E n.c. NO ATM ATM 35 30 25 2012 22 32 60 50 2013 52 20 15 10 5 0 14 7 4 4 1 1 1 2 1 A B C D E n.c. NO ATM ATM 40 30 20 10 0 22 2 1 1 6 1 1 3 A B C D E n.c. NO ATM ATM
2010 2011 12% 16% 10% 5% Aircraft Helicopter Person 1% Aircraft Helicopter Person Vehicle Vehicle 73% 83% 2012 17% 2013 1% 2% Aircraft Helicopter Person Vehicle 9% 22% Aircraft Helicopter Person 80% 69% Vehicle
If you only fix the symptoms what you see on the surface the problem will almost certainly happen again... which will lead you to fix it, again, and again, and again. If, instead, you look deeper to figure out why the problem is occurring, you can fix the underlying systems and processes that cause the problem.