标题: B757 Contaminated And Slippery Runways [打印本页] 作者: 民航 时间: 2010-4-5 20:48:06 标题: B757 Contaminated And Slippery Runways
B757-Contaminated_And_Slippery_Runways
作者: 民航 时间: 2010-4-5 20:48:35
Giesman757.1 Contaminated and Slippery Runways Paul Giesman Performance Engineer Operations Flight Operations Engineering Boeing Commercial Airplanes May 2004 The Boeing Company “I glanced at the air speed indicator and saw it registered 105 knots and was flickering. When it reached 117 knots I called out `V1‘ [Velocity One, the point on the runway after which it isn’t safe to abandon take-off]. Suddenly the needle dropped to about 112 and then 105. Ken shouted, `Christ, we can‘t make it’ and I looked up from the instruments to see a lot of snow and a house and a tree right in the path of the aircraft”. Inside the passengers‘ compartment Bill Foulkes had sensed that something was wrong: “There was a lot of slush flying past the windows and there was a terrible noise, like when a car leaves a smooth road and starts to run over rough ground”. The Elizabethan left the runway, went through a fence and crossed a road before the port wing struck a house. The wing and part of the tail were torn off and the house caught fire. The cockpit struck a tree and the starboard side of the fuselage hit a wooden hut containing a truck loaded with fuel and tyres. This exploded. Giesman757.2 The Boeing Company Giesman757.3 Non-Dry Runway Topics • Wet runway – Regulatory/operations • Slush / standing water • Snow covered runway – Loose/compact • Slippery runways • Crosswind considerations The Boeing Company Giesman757.4 Wet Runway Regulatory Requirements • FAA historically – No definitive regulatory requirements for wet runway performance adjustments in Part 25 or 121 – Boeing supplied as a subset of slippery runway data The Boeing Company Giesman757.5 Wet Runway Regulatory Requirements • FAA current (737-6/7/8/900, 757-300, 767-400) – Wet runway is part of AFM certification basis – Amendment 25-92 – Assumptions – 15 foot screen height – Engine inoperative reverse thrust credit • JAA Operators − New certifications - same as FAA (Note: 747-400 also certified to a different wet runway standard) Note: This data is based on an agreed upon certification method which adjusts a standard wet runway braking characteristic curve by the individual airplanes anti-skid system efficiency. The Boeing Company Giesman757.6 Wet Runway Regulatory Requirements • Operational data - JAROPS 1 – Requires operational wet runway data based on possibility of an engine failure – Boeing supplies performance information for wet as a subset of slippery runway data – Recommend use of the data based on pilot reported braking action of Good (approximately ½ the dry runway effective ness when runway friction limited) – This performance level is consistent with CAA certification flight testing accomplished on the 707, 727, 737-1/2/200Adv, 747-100/200 The Boeing Company Giesman757.7 Boeing Slush/Standing Water Data AFM information FAA – No AFM requirements JAA – AFM contains advisory data for more recent airplanes 747-400, 777, 737NG, 757-300, 767-400 The Boeing Company Giesman757.8 Boeing Slush/Standing Water Data Operational information • Boeing supplies data in the OM, FPPM, PEM and performance software • Data in manuals are weight reductions and V1 adjustments • Assumptions in calculation of performance – One engine inoperative – 15 screen height at the end of the runway – Reverse thrust on operating engines Note: All engines slush standing water data is still available – very few use this data – Weight reduction – NoV1 adjustment provided – Preserves 15% margin No V1 The Boeing Company Giesman757.9 Snow data • Provided in operational software for – 737-6/7/8/900, 777, 757-300, 767-400 – Loose dry snow – Calculations based on slush modeling using snow specific gravities — depths to 101 mm – Compact snow based on a relationship agreed upon during JAA certification that is equivalent to a pilot reported braking action of “good” The Boeing Company Giesman757.10 Slippery Runway • Weight reduction and V1 adjustment provided – Reduced tire to ground friction – Credit for reverse thrust – Go to 15-ft screen height • Data a function of pilot reported braking action – Good — wet – Medium — comparable to 727 ice and compact snow testing — 60’s – Poor — wet melting ice • Boeing does not correlate performance data with friction cart information Datta prresentted iin aiirrpllane Operrattiionss Manuall,, FPPM,, and PEM ((Weett,, IIccyy)) The Boeing Company Giesman757.11 Crosswind Guidelines • Boeing publishes takeoff and landing crosswind guidelines in the Flight Crew Training Manuals – Derived from analysis and piloted simulations – Based on steady winds – Function of runway condition — dry, wet, standing water/slush, snow — no melting, ice — no melting – Accounts for asymmetric reverse thrust – Provides guidance on technique (side slip, crab) The Boeing Company Giesman757.12 Example Of FCTM Information May Be Different For TO And Land Ice — No Melting** 15 Snow — No Melting** 20 Standing Water/Slush 15 Wet 25 Dry 40 Runway Condition Crosswind — Knots* The Boeing Company Giesman757.13 Crosswind Guidelines Recently Boeing extended additional guidance relating runway condition to Pilot reported Braking Action FCTM Runway Condition Braking (TO and Land Guidelines) Dry Dry Wet Good Snow — No Melting Medium to Good Slush/St. Water or Medium to Poor Ice — No Melting Pilot Reported Action作者: hehe1019 时间: 2010-5-6 14:57:38