boeing perf cse v1 go-no go
DESCRIPTION
V1 Go NoGo trainingAircraft PerformanceRejected takeoffTRANSCRIPT
FLIGHTOPERATIONS
ENGINEERING
1For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
V1 Go-No Go
Performance Engineer Operations
Bruce LindstromFlight Operations Engineering
Boeing Commercial AirplanesSeptember 2009
2For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
RTO-R
ELAT
ED
ACCI
DENT
S
CONT
INUE
TO O
CCUR
!
DAILY NEWSNEW YORK’S PICTURE NEWSPAPER35 cents Friday, September 22, 1989
3For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Objectives
• Stress the importance of V1
• Learn from Statistics of past Rejected Takeoff (RTO) accidents and incidents
• Educate for a better “Go/No Go” decision
• Avoid future overruns and RTO’s!
4For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Reasons for RTOs?
NTSB post accident/incident discoveries
• Rejects were unnecessary
• V1 technique improper
The NTSB concluded:“…Pilots faced with unusual or unique situations
may perform high-speed RTO’s unnecessarily or may perform them improperly.”
February 1990
5For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
The “Human Factor Approach”
Takeoff Safety
6For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Takeoff Safety Training Aid Development1990 - 1992
Draft review mailing grew to 137
• 35 airlines (12 U.S.)
• 3 pilot associations
• 7 government agencies
• 5 industry associations
• 10 manufacturers
7For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Takeoff Safety Training Aid Contents
Section 1 Overview for Management
Section 2 Pilot Guide to Takeoff Safety
Section 3 Example Takeoff Safety Training Program
Section 4 Takeoff Safety - Background Data
Video “Rejected Takeoff and the ‘Go/No-Go’ Decision”
Flexibility to incorporate lessons into your initial, transition, and recurrent training programs to meet your needs.
8For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Objectives of Takeoff SafetyTraining Aid
• Benefit from Lessons Learned– Past Accidents– RTO Safety Task Force– Pilot Performance Study
• Improve ability of pilots to take maximum advantage of all takeoff performance margins
• Make best “Go/No-Go” decisions
• Effectively accomplish related procedure
9For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
97 RTO Overrun Accidents/IncidentsSince 1959
74 overruns included in original NTSB study23 overruns since NTSB study
10For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Takeoffs, RTOs, and Overruns
Takeoffs
RTOs (estimate)
RTO Overrun Accidents/Incidents
Through 2003
430,000,000
143,000
97
18,000,000
6,000
4
Typical Recent Year
11For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Takeoffs and RTO Overrun Incidents/Accidents ( By Decade )
Rate per 10 million takeoffsRTO overrun accidents/incidents per 10 million takeoffs
Decade Departures RTO overrun accidents/incidents
1960 - 19691970 - 19791980 - 19891990 - 1999
19,045,36375,984,954108,963,013161,957,587
12322822
6.34.22.61.4
1960’s 1970’s 1980’s 1990’s020
4060
80100
120140
160180
Millions of takeoffs
0
1
2
3
4
5
6
7
Rate per10 million takeoffs
6.3
4.2
1.4
2.6
109
162
19
76
12For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Total Industry RTO’s
80 knots or less
Percent of total
80
60
40
20
0
76%
80 to 100 knots
100 to 120 knots
Above 120 knots
18%
4%2%
RTO overrun accidentsprincipally come from the 2% of the RTO'sthat are high speed
As a Function of Speed
13For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
RTO Accidents/Incidents - 97 Events
Unknown21%
Greater than V1
55%Less than/equal to V1
25%
Initiation Speed
14For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
RTO Accidents/Incidents - 97 Events
Not reported30%
Dry38%
Snow8% Wet
24%
Runway Condition
15For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Engine
Wheel/tire
Configuration
Indicator/light
Crew coordination
Bird strike
ATC
Other/not reported
21%
22%
0 5 10 15 20
Percent of total (97 events)
12%
14%
10%
7%
11%
2%
Reasons for Initiating RTO – 97 Events
Non-Engine*79%
Engine21%
*Including events “Not reported”
16For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Review of the 97 Events Revealed:
By continuing the takeoff
52%
Unavoidable18%
By correct stop techniques15%
By better preflight planning15%
82% were avoidable
17For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
What Do The Statistics Mean?
• RTOs are not common
• Infrequency leads to complacency
• Pilot must be prepared
18For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Key Subjects for Flight Crews
• Regulatory Rules and Certification Criteria
• Takeoff Performance
• Effects of Airplane and System Configuration
• Takeoff Safety Margins
19For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Decision Time?
“Oops, I think I should have already made my decision”
20For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
V1 Misnomer and Definition
V1 is interpreted differently:– Pilots– Engineers– Regulatory Agencies
V1 - is the speed at which the takeoff should be continued unless the stopping maneuver has already been initiated.
21For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
V1 Is Two Concepts
V1 - Stop( Maximum “STOP” Speed )
V1 - Go( Minimum “GO” Speed ) 35 ft
22For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Historical FAR V1 Definition :
(Prior to March 1, 1978)
[FAR Paragraph 25.107(a)]
V1 – Critical engine failure speed.“V1 is the critical engine failure speed. It shall not
be less than the minimum speed at which controllability by aerodynamic controls alone is demonstrated during the takeoff run to be adequate to permit proceeding safely with the takeoff using average pilot skill, when the critical engine is suddenly made inoperative.”
23For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Historical FAR V1 Definition :
(March 1, 1978)
[FAR Paragraph 25.107(a)(2)]
V1 – Takeoff decision speed.
“It cannot be less than VEF plus the speed gained with the critical engine inoperative during the time interval between the instant the critical engine has failed and the instant the pilot has recognized and reacted to the engine failure by application of the first retarding means.”
24For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Current FAR V1 Definition :
(March 20, 1998)
[FAR Paragraph 25.107(a)(2)]
V1 – No longer described as “Takeoff decision speed”
“It cannot be less than VEF plus the speed gained with the critical engine inoperative during the time interval between the instant the critical engine has failed and the instant the pilot has recognized and reacted to the engine failure, as indicated by the pilot’s initiation of the first action to stop the airplane.”
25For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Takeoff Rules
All enginesGo Distance
V1
VR VLOF
• 35 feet
• V2 + 10 to 25 knots*
*(Varies with airplane type)
FAR Takeoff Field Length (Case #1)
+15%
Actual distance * 1.15
26For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Takeoff Rules
V1
1 sec
One engine inoperativeAccelerate-Go Distance VEF VR VLOF
• 35 feet
• V2
FAR Takeoff Field Length (Case #2)
27For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
One engine inoperative/ all-engine
Accelerate-Stop DistanceV
event
Takeoff Rules
FAR Takeoff Field Length (Case #3)
RTO transition complete
Transition
V1
1 sec
Stop
28For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Takeoff Rules
FAR Takeoff Field Length
RTO transition complete
One engine inoperative/ all engineAccelerate-Stop Distance
V1
VEVENT
TransitionStop
1 sec
• 35 feet
• V2 + 10 to 25 knots*
*(Varies with airplane type)
All enginesGo Distance (115% actual)
1.15 times the actual distance
• 35 feet
• V2
One engine inoperativeAccelerate-Go Distance
V1
VEF VR VLOF
1 sec
29For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Transition to Stopping Configuration
DecisionV1
Speedbrakes raisedBrakes applied
Thrust levers to
idle
Distance allowance
30For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Service allowance
Rejected Takeoff Sequence
CertificationFlight Test
Full braking configuration
AFMExpansion
AFM expansion approximately 4 seconds
Full braking configuration
TimeF/T Demo 2.0 seconds
Speedbrakesup
Throttles to idle
Flt Test demonstrated transition1 to 1.4 seconds
Enginefailure
Recognition( min 1 second)
V1
Brakes onDry runway performance in AFM does not include thrust reverser credit…
31For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Model Specific Transition Times
32For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Accelerate-Stop Transition Distance
“Pre 1981”707, 727, 737-100/200747-100/200/SP/300DC-8, DC-9, DC-10MD-80
“Post 1981”757, 767, 747-400737-300/400/500
Amendment 25-42777-200/300 (1995)MD-11, MD-90
Acceleration Transition
1sec
3 sec(typical)
Brakes Throttle
2 seccontinued
accelerationFlt test
transition
Flt testtransition
VEF
VEF
VEVENT
V1
2 secat VB
Amendment 25-92737 NG, 757-300767-400 (1998), 717
2 secat V1 Flt test
transitionVEVENT
Typically100 -150 ft
longer
Stopping
Speed brakes
Typically60 – 100 ft
shorter
Typically130 – 400 ft
shorter
Baseline
33For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Takeoff Safety Training Aid Video
34For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Key Subjects for Flight Crews
• Regulatory Rules and Certification Criteria
• Takeoff Performance
• Effects of Airplane and System Configuration
• Takeoff Safety Margins
35For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Maximum Allowable Takeoff Weight
Lowest of all the weight limitations• Performance (Varies from day-to-day)
– Runway• Field Length• Tire Speed• Brake Energy• Obstacle
– Climb
• Structural (AFM Restriction – Maximum Certified)
• Other– Noise– Runway Loading– Landing at destination– Enroute Requirements
36For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
115% all-engine
Effect of V1 Speed on Takeoff Weight (for a fixed runway length)
Airplaneweight
V1 speed
Incr
easi
ng
Increasing
Continued takeoff
Rejectedtakeoff
Field limit weight
Bala
nced
fiel
dV
1 sp
eed
Climb Limit
37For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Balanced Field
Engine-out go distance = Accelerate-stop distanceEngine-out go distance = Accelerate-stop distance
But the actual runway available is usually longer than the minimum Balanced Field Length Required
38For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Details of the “Go” versus “Stop” Decision
Runway used to accelerate to V1 (typically 60%)
Runway available to Go/Stop (typically
40%)
One engine inoperativeAccelerate-Go Distance
V1
VEF
1 second minimum
• 35 feet
• V2
VR VLOF
1 second minimum
V1
VEVENT
Accelerate-Stop Distance
Stop
RTO transition complete (AFM)
Transition
39For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
15 degree bank turn will reduce these climb rates by approximately 100 FPM
2 engine
3 engine
4 engine
Minimum gradient required
3%
2.7%
2.4%
Typical rate of climb
520 FPM at V2~170 knots
440 FPM at V2~160 knots
360 FPM at V2~150 knots
Climb Gradients
40For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Runway Surface ConditionWet or Contaminated
Affects friction between runway and tires
41For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Dynamic Hydroplaning
• Tire Braking Virtually Eliminated
• Highly Sensitive to Speed
Flooded runway
Must Apply Steady Brake Pressure!
42For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Key Subjects for Flight Crews
• Regulatory Rules and Certification Criteria
• Takeoff Performance
• Effects of Airplane and System Configuration
• Takeoff Safety Margins
43For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Maximum Stopping Performance
• Max brakes
• Thrust idle
• Speedbrakes
• Reverse thrust
44For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Heat Buildup
Long taxi
Excessive braking
Tires and Brakes
Wheel cracks
Foreign objects
Visual Inspection
45For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Residual Brake Energy
• Observe BrakeTemperature Limitationsand/or Minimum CoolingTimes
• Follow Maximum QuickTurnaround Weight(MQTW) Chart
46For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
• Same initial conditionsTire fails
V1
• Landing flaps• Certified performance less
blown tire effects• Takeoff weight minus burnoff
and fuel dump (opt)50 ft
40 to 60% StopZone
Reject
Margin 60 to 40 %Available Runway
• Takeoff flaps• Certified performance• Dry runway• Field length limit weight
V1VEF
Engine fails
VR35 ftGo
Reject
Transition complete
Full stoppingno reverse
GoVR
Approx 150 ft
Transition complete
Reduced brakingcapability plus all engine reverse
40 to60 kts
300 to 500 ft overrun
Go and Stop Margins with a Tire Failure
47For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
400- to 600-feet overrun
60-70 kts
Speedbrakes
Stopping with airplane brakes but no speedbrakes
48For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Speedbrake Effects
Speed-brakes down Lift
Load on wheels
DragBrakes
Speed-brakes up
34% increase
Total stopping force capability
BrakesDrag
Forward motion
Rolling
Weight on tire
Brake torque
Braking force
(Braking force = braking friction x load on tire)*
* Brake torque not limiting
Down Up
Speedbrake position Difference speedbrake up
DragLiftNet load on wheelsMaximum braking forceMaximum stopping force(brakes and drag)
8,500 lbs52,000 lbs
141,60075,500
84,400
14,700 lbs-1,200
194,80098,000
112,700
+73%-102%+38%+29%
+34%
49For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Speedbrakes Versus Reverse Thrust
Field length limit dry runway
One engine-out RTO
Brakes + speedbrakes + reverse thrust
One engine-out RTO
Brakes + reverse thrust
300- to 600-ft overrun
100- to 300-ft margin
50For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Minimum Equipment List (MEL) and Configuration Deviation List (CDL)
• May affect ability to accelerate/decelerate
** Check Revised Procedures **
51For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Key Subjects for Flight Crews
• Regulatory Rules and Certification Criteria
• Takeoff Performance
• Effects of Airplane and System Configuration
• Takeoff Safety Margins
52For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
0
Speed off end of runway, knots
Abort initiation speed above scheduled V1, knots
4 8 12
120
80
40
0
One second delay
Maximum effort stop
Takeoff “Stop” Margins
Shaded area indicates degraded stopping performance• Contaminated runway• Pilot technique• System failures
53For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
One second early
Height at end of runway (feet)
Speed relative to V1 (knots)
0
10
20
30(35)
40
(150)
One engine inoperative
All engines
-20 -16 -12 -8 -4 0 +4 +8
V2 + 10 to 25 knots
V2
4 engine airplane
3 engine airplane
2 engine airplane
Takeoff “Go” Margins
54For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
TAKEOFF REF f / f O A T V 1
2 3 º C 130 K TSEL TEMP V R
- - - º C 131 K TSEL TEMP V 292 . 5 / 9 2 . 5 % 139 K T- - - - - - - P R E - F L T C O M P L E T E - - - - - - -
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -> I N D E X
FMS Speeds and Weights
• NO Safety Margin Data Available
55For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Flap Selection Typical Large Two-engine Airplane Takeoff Performance
Flap setting8,700ft. runway sea level 37° C
1 5 15 20
Runway limit weight, lb. (kg)
358,300(162,494)
374,200(169,705)
389,000(176,417)
393,600(178,503)
Climb/obstaclelimit weight, lb. (kg)
414,100(187,800)
407,300(184,717)
393,600(178,503)
383,000(173,696)
56For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
RTO Safety Task Force Recommendations
• Develop “model”training practices
• Develop “model”operational guidelines
• Improve simulator fidelity• Provide runway
condition reports• Residual brake heat
accountability
AdvisoryRegulatory• Standardize accelerate-
stop transition• Wet runway accountability• Worn brake accountability• Line up distance
accountability
57For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Better Simulator Fidelity
Validates Desired Performance
58For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Operations and Training Recommendations
Pilots need more education and training on:Training: Ground• Meaning of V1
• Basic performance• Contaminants• Reverse thrust• Flap selection
and reduced V1
Operational• High speed callout• Timely V1 callout• Correct procedures• Standardize callout• Use of RTO
autobrakes• Pre-takeoff briefing
Training: Simulator• Maximum braking
techniques• RTO on balanced
field• Tire failures• Warnings/cautions
59For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
The Crew
• Preflight briefing
• Cockpit callouts
• Positive action if malfunction occurs
60For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
The Briefing
• Clear
• Concise
Agreement of Responsibilities( MEL, weather, noise abatement, etc.)
61For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Use Standard Callouts(Normal, malfunctions, V1)
Communication
• Precise
• Clear
62For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Timely V1 Callout
Finish the callout as the airplane reaches V1
600
80100
120
140160
180200
400350
300
250240
220
KNOTS
MACH
1 2 67
5
Ensures a “No Go”decision will not bemade after V1
63For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Items to Reject For
Low speed:
• System failures
• Unusual noise or vibration
• Tire failures
• Abnormal acceleration
• Fire or fire warning
• Engine failure
• Unsafe takeoff configuration
• Unsafe or unable to fly
High speed:•Engine failure or fire•Unsafe or unable to fly
The FCOM RTO procedure may list other items to reject for in the high speed regime:
• Predictive Windshear Warning• Fire or Fire Warning
64For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
FSAT 96-05 - Operator Use of "Takeoff Training Aid"
{New-96-6 Added June 30, 1996}Flight Standards Information Bulletin (FSIB) for Air Transportation (FSAT)EFFECTIVE DATE: 05-08-96TRACKING: NTSB Recommendations A-90-41 through -48NOTE: THIS BULLETIN REQUIRES PTRS INPUT. SEE ITEM 3.
1. BACKGROUND. National Tran sportation Safety Board (NTSB) Safety Recommendations A-90-41 through -48 address Federal Aviation Administration (FAA) oversight of airline pilot training in rejected takeoff (RTO) maneuvers.The FAA published Advisory Circular (AC) 120-62, "Takeoff Training Aid," which responds to these recommendations. The Safety Board is concerned that some operators are not using the material contained in the AC in their training and procedures. To reassure the NTSB that the AC has been implemented by all Title 14 Code of Federal Regulations part 121 (14 CFR part 121) operators, the FAA is documenting the material's implementation and use by all operators in pilot training programs and operations.
2. ACTION. Principal operations inspectors (POI) are requested to document that all operators are using the information contained in AC 120-62 in both training and procedures. This documentation is requested within sixty (60) working days of the effective date of this bulletin.
3. PROGRAM TRACKING AND REPORTING SUBSYSTEM (PTRS). POI’sshall make a PTRS entry to document that each operator is using the information in AC 120-62 in both training and procedures. POI's shall follow the procedures as outlined in HBAT 94-08, Program Tracking and Reporting Subsystem (PTRS) Documentation of Action Required by Flight Standards Bulletins. The PTRS entry shall be listed as Activity Code Number 1381; the "national use" field entry should be “FSAT9605.” POI's should use the comments' section to record comments of interaction with the operators
4. INQUIRIES. Questions or comments regarding this FSAT should be directed to AFS-210 at (202) 267-7480.
5. EXPIRATION DATE. This FSAT will expire May 31, 1997.
/s/David R. Harrington
Advisory Circular 120-62
To reassure the NTSB that the AC has been implemented by all Title 14 Code of Federal Regulations part 121 (14 CFR part 121) operators,
Principal operations inspectors (POI) are requested to document that all operators are using the information contained in AC 120-62 in both training and procedures.
65For Training Purposes Only © Copyright 2009 Boeing All Rights Reserved
Final Thoughts
• 82% of events were avoidable
• Full thrust available in 79% of cases
• Over half of rejects were initiated after V1
• Many takeoffs performed at less than limiting weight
• More margins exist with “Go” decision