risk management for small flight test teams: lessons learned spinning light aeroplanes robert erdos...
TRANSCRIPT
RISK MANAGEMENT FOR SMALL FLIGHT TEST TEAMS: LESSONS LEARNED SPINNING LIGHT AEROPLANES
Robert Erdos MSc, PEng, DAR
Chief Test Pilot
Flight Research Laboratory
National Research Council of Canada
Ottawa, Canada
At Issue…
FTSW often facilitates discussion of flight test safety practices and risk management principles.
Most participants are from large organizations with large resources.
But, what if… You are the flight test team; and The client has limited resources or experience.
Presentation Outline
1. Outline an example of a small aircraft certification team;
2. Review applicable risk management strategies;
3. Relate an incident; and
4. Discuss lessons learned.
Flight Research Laboratory Part of the National Research Council of Canada
Canada’s agency for “research, development and technology-based innovation”
Operates 9 specialized research aircraft
Diverse program of research Commercial and government clients From fundamental research to product
development/certification
Fee-for-service work makes Lab’s personnel accessible
to small companies
Contracted by Ultravia Aero Int’l in 1999.
The Project:Certification of the Ultravia Pelican
Successful Canadian kitplane manufacturer
Sought to certify under CAR 523-VLA
Two-place single-engine high-wing trainer Rotax 912 engine Max. gross weight 1450 lb Design Vs0 = 43 KCAS
Ultravia = 5 full-time employees
NRC provided consulting flight test services
No one on the project had prior certification
experience
The Project:Certification of the Ultravia Pelican Successful Canadian kitplane manufacturer
Sought to certify under CAR 523-VLA
Two-place single-engine high-wing trainer Rotax 912 engine Max. gross weight 1450 lb
Ultravia = 5 full-time employees
NRC provided consulting flight test services
No one on the project had prior certification
experience.
• Originated with JAA as JAR-VLA
• Adopted by Transport Canada in 1993
•Based upon FAA Part 23, with a few Canadian amendments
The Situation
Very limited in-house resources Time constraints Financial constraints Desire to please the client
Risk Management Resources: Internal
NRC Test Pilot
President & Chief Designer,
Ultravia
Transition from military or research test flying to civil certification can present challenges
Online resources present acceptable certification methodologies and lessons-learned
A good working relationship with the regulatory authority is essential
Risk Management Resources: External
The Risk Management “Contract”
It is far more productive to discuss “risk” than “safety”.
The consulting test pilot can assume responsibility for the client’s most valuable
asset.
Organizational cultures and expectations may vary.
Risk management protocols need to be stated explicitly. A “contract” is the application of “plan the flight, fly the plan.” It may be wise to have the client sign it.
The Risk Management “Contract”, Cont’d
Following a partial power loss or non-critical malfunction indication, a contingency approach to the nearest prepared landing area will be initiated. An off-airport landing will not be executed unless imminent complete loss of power or danger of significant damage to the aircraft precludes a landing on a runway;
Following a complete loss of engine power, a force-landing will be executed to the most suitable available area;
In the event of an inability to recover from a spin, or entry into an unrecognizable flight regime, efforts will continue to recover the aircraft to controlled flight to a minimum altitude of 4000 feet AGL. Upon reaching 4000 feet AGL, the test pilot will abandon the aircraft; and
Following a catastrophic structural failure, failure of the flight control system or uncontrollable fire, the test pilot will immediately abandon the aircraft.
Spin Tests:Spin Chute Installation, Yes?
CAR 523-VLA certification for non-
intentional spins requires recovery “from
a one-turn spin or a three-second spin,
whichever takes longer, in not more than
one additional turn after initiation of the
first control action for recovery”.
Typically relies upon an airframe-
mounted spin recovery parachute
Small aircraft present W&B challenges
Pelican Weight and Balance:Spin Chute Installation, No.
System includes chute, structure,
deployment and jettison mechanisms,
rocket motor and interface
Prohibitively large mass at aft
fuselage station. Need to test at “4 corners” of W&B Engine ballast offset prohibits light
weights
BRS considered Does not avoid considerable aircraft
damage
Bail-out chute the only practical option
Sortie #71:One-Turn Spins, Revisited
Sortie was a continuation of spins conducted Heavy-Forward CG
Power ON spins repeatable with recovery after ~1 turn. Strong influence of power. Can’t spin <3000 RPM Recovery slightly slower in left spins Very rapid spin rates after 1 turn (~240 deg/sec) Prior sortie repeated to ascertain recovery compliance
Did not feel that recovery was in question
10’th repetition of the same test point Clean 1-turn erect spin to the right
Recovery initiated after 1 turn…no effect Prop stopped after 2-3 turns Counter-spin control inputs held firmly “Accidentally” discovered limited pitch rocking
authority Recovered, restarted engine, went home…
Sortie #71:Spinning, spinning, spinning…
Sober Second Thought:
A plane lacking the control power to spin may lack the control power to recover
Rehearse all the recovery actions
Full forward stick may not be helpful until after rotation stops
Risk management for small test teams presents special challenges
Spin testing of very light plans not yet adequately addressed
Thank You
Robert Erdos MSc, PEng, DAR
Chief Test Pilot
Flight Research Laboratory
National Research Council of Canada
Ottawa, Canada
613-998-3180
The Bail-Out Option Reconsidered
Spin trajectory not vertical Descending helix
determined by inertial and aerodynamic forces
Highly wing-loaded airplanes will have a higher tangential velocity.
The Bail-Out Option Reconsidered, Cont’d
Lightly-loaded aircraft can have a very tight spin and a low tangential velocity
Confidence in a manual bail-out may not be warranted.
Uh oh!