The French TALPA Trial Results of Winter 2014-2015 Hai PHAM DOAN Civil Aviation Technical Center Airport Infrastructures Department Division of Studies and Research Symposium on Assessment and Report of Runway Surface Conditions, 31 March 2016- Paris-DGAC Direction générale de l Aviation civile - Service technique de l Aviation civile 1 www.stac.aviation-civile.gouv.fr
Airport Manager Type of contaminant Depth of Contaminant Friction coefficient Air Temperature, Surface Temp. Freezing Point Assessment TALPA Matrix (RCAM) Judgment Runway Condition Code 0 1 2 3 4 5 6 Aircraft Performance at Landing or Take-Off Braking Action... 2
THE FRENCH TALPA TRIAL Purpose: To determine the correlation between braking action assessed by airport operators (through RWYCC) and braking action reported by pilots (through PIREPs), in relation to local contaminants and weather in France. Methodology: by collecting runway inspection data from airport operators and air traffic controllers With whom: 12 French Airports (2 overseas) When: during 3 winters between 2014 and 2017 (period from November to April) Direction générale de l Aviation civile - Service technique de l Aviation civile 3 www.stac.aviation-civile.gouv.fr
12 PARTICIPATING AIRPORTS LFPG LFST Overseas territories LFRN LFRK LFPO LFSB TFFF LFVP LFLL LFLW LFKJ LFML 4
METHODOLOGY Airport Sheet Air Controller Sheet Type and Depth of Contaminant PIREP Runway Condition Code 0 1 2 3 4 5 6 Consistency? PIREP Good... Poor 0 1 2 3 4 5 6 5
AIRPORT SHEET Airpo rt Dat e Loc a l time Oper ator Piste % of contamination C o n t a m i n a n t depth (mm) Type of contaminant Air Temperature Mu (<1) Information E 1 E 2 E 3 H 1 H 2 H 3 C 1 C 2 C 3 T 1 T 2 T 3 M1 M2 M3 6
AIR CONTROLLER SHEET Date (JJ/MM/ AAAA) Local Time (HH/ MM) Flight Nuber Type of aircraft Airline Company Runway PIREP* Information 7
ANALYSIS OF PAIRS Airport-based information (Runway inspector) Example : time interval of 60 minutes Airborne information on the braking performance (Pilot) Time RWYCC Time PIREP 08:00 3 10:00 2 11:00 5 14:00 4 08:30 3 10:15 3 13:00 4 14:20 3 8
Results Winter 2014-2015 Journée technique du STAC 2015 www.stac.aviation-civile.gouv.fr 9
NUMBER OF PAIRS AS A FUNCTION OF TIME INTERVAL Interval (min) RWYCC- PIREPs pairs 30 64 45 83 60 91 75 107 10
RESULTS 1000 Runway reports (RWYCC) Time interval : 60 min 307 PIREPs 91 Pairs All airports 11
Frequency of PIREPs North- West North- East Airport 12
FREQUENCY OF PIREPS, EXCLUDING GOOD 50 45 40 35 30 Frequency % 25 20 15 10 5 0 Good to Medium Medium Medium to Poor Poor Less than Poor PIREP 13
RWYCC VS. PIREPS RWYCC is lower than PIREP: the assessment of braking action by the pilot is better than the assessment provided by runway inspector RWYCC is higher than PIREP : the pilot assesses conditions as worse than the runway inspector RWYCC is equal to PIREP : the pilot has the same assessment as the runway inspector Direction générale de l Aviation civile - Service technique de l Aviation civile 14 www.stac.aviation-civile.gouv.fr
CORRELATION BETWEEN RWYCC AND PIREPS (XP FRANCE) TALPA Matrix is conservative in 72% of cases 11% 61% = 28% < > 15
CORRELATION BETWEEN RWYCC AND PIREPS (XP USA) TALPA Matrix is conservative in 89% of cases 29% 60% 4% < = > 16
ENCOUNTERED CONTAMINANTS (XP FRANCE) EXCLUDING DRY Wet runway, slush, snow less than 3mm 90% Dry snow or wet snow more than 3mm etc... Ice 1% 2% 1% 4% 0% RWYCC 0 1 2 3 4 5 17
ENCOUNTERED CONTAMINANTS (XP USA) EXCLUDING DRY Wet runway, slush, snow less than 3mm 67% Dry snow or wet snow more than 3mm etc... Ice 23% 1% 8% 1% 0% RWYCC 0 1 2 3 4 5 18
ENCOUNTERED CONTAMINANTS EXCLUDING DRY (XP FRANCE VS XP USA) Wet runway, slush, snow less than 3mm 90% Dry snow or water more than 3mm etc... Ice 1% 2% 1% 4% 0% RWYCC 0 1 2 3 4 5 19
70 DISCREPANCIES RWYCC-PIREPS 60 50 in 80% of cases, difference is less than 1 point (-1,0,+1) 40 % 30 Safe 61 Not safe 20 10 0 0 7 4-3 -2-1 0 1 2 3 Différence RWYCC-PIREP 15 RWYCC 5 - PIREP 3 essentially 9 RWYCC 5 - PIREP 2 essentially 3 20
70 60 50 Frequency (%) DISCREPANCIES RWYCC-PIREPS (XP ITALY VS XP FRANCE) 62 62 Nota : UK trial showed «a better than 60% correlation» (Notice CAA-UK, 12/1/2015, para. 2.4) 40 30 XP ITALIE XP FRANCE 20 15 16 10 0 1 8 9 7 7 4 5 3 0-3 -2-1 0 1 2 3 4 Difference 21
70 XP FRANCE VS. XP ITALY 62 62 60 50 Pourcentage of pairs 40 30 20 22 16 27 XP Italie XP France 10 11 0 RWYCC inf. PIREP RWYCC=PIREP RWYCC sup. PIREP 22
CONCLUSION 72% of RWYCC matched or were lower than PIREP (conservatives data) But relatively small number of data and pairs and few contaminants encountered (mild winter) Discrepancies RWYCC-PIREPs in case of water (difficulties for pilots to assess braking performances) Difficulty of pilots to perform braking action that were correlated with PIREP in WET conditions The consistency of the matrix has to be studied with ICE, DRY SNOW and WET SNOW STAC will pursue the trial during winters 2016-2017 and 2017-2018 Direction générale de l Aviation civile - Service technique de l Aviation civile 23 www.stac.aviation-civile.gouv.fr
For any question about the French TALPA Trial, please contact: Hai PHAM DOAN Service technique de l aviation civile Département Infrastructures aérportuaires Division Etudes et recherche hai.pham-doan@aviation-civile.gouv.fr phone number : +33 (0)1 49 56 81 51 Direction générale de l Aviation civile - Service technique de l Aviation civile 24 www.stac.aviation-civile.gouv.fr