Phase One - Safety

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TXFlyGuy

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This is purely hypothetical...

How many of you owners/pilots would knowingly fly your aircraft during phase one with a known failure of a major flight control system?

My background is Part 121 Airline, and that is a grounding item.

But in the experimental world...what say you?
 

radfordc

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Yeah, I'll fly the thing no matter how bad it's built!

OK, that's a dumb answer....sort of like the question!

Really hypothetical, or do you have a story?
 

Topaz

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This is purely hypothetical...
Uh huh. And "asking for a friend," no doubt.

How many of you owners/pilots would knowingly fly your aircraft during phase one with a known failure of a major flight control system?
Only the ones who have a death wish. Duh.

You don't really need an answer to this question, do you? Either you're being hyperbolic about "major" flight control system, or deliberately obtuse. Either way, it smacks of trolling. Please clarify so that we're not playing twenty questions just to find out what's wrong with your airplane and why you're considering flying it with that issue.
 

TXFlyGuy

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No, it's not a dumb question. And there is no story.

I am looking for serious answers, supported by logic.

Flight control system - Flaps Inoperative

Would you fly, or ground the plane for repairs? There is no legal reason (FAR) not to fly, if that makes you feel better.

To me, the flaps are a major system. Maybe they are minor to some pilots.
 

Topaz

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Inop how? Locked up? Locked down? Not working synchronously? What kind of airplane (level of performance)?

If there's no story here, why are you asking?
 

TXFlyGuy

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Flaps inop, broken flap drive. Will not remain in the down position.

Do you fly? Do you ground the plane?

This is a forum for matters like this. That's why the question was asked.
 

BJC

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No, it's not a dumb question. And there is no story.

I am looking for serious answers, supported by logic.

Flight control system - Flaps Inoperative

Would you fly, or ground the plane for repairs? There is no legal reason (FAR) not to fly, if that makes you feel better.

To me, the flaps are a major system. Maybe they are minor to some pilots.
Depends on the failure mode of the flaps, and the aircraft.

I would fly a Carbon Cub with inop. flaps that do not interfere with other controls, but probably not some other airplanes.


BJC
 

TXFlyGuy

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If everything else was working perfectly, perhaps I would fly the plane also.

But this appears to have occurred during the test phase, so in this case I would ground the plane until repairs could be made.

But for all of you wannabee test pilots, what say you? Fly a plane with a known defective flight control during Phase One? No FAR against it, so you are legal.
 

Topaz

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... But for all of you wannabee test pilots, what say you? Fly a plane with a known defective flight control during Phase One? No FAR against it, so you are legal.
No. Because the flight test period means all characteristics, capabilities, and flaws of the airplane are not known and demonstrated good. There may not be an FAR against flying this way, but there's no reason to fly this way either. One inop system means you're just another inop system from two and, if you took off with one, it means you're going to find the second in-flight. Whatever that second one might be, the first may limit your options in dealing with the second in a way that limits your options to go on living.

If it's a known airplane with a good history, especially something lower performance, and there's some reason it needs be flown as-is with the flaps inop and locked "up," then maybe. But in the flight test period there is zero reason to fly with any system inop, large or small, especially for a non-commercial homebuilt project like any on these boards. A trivial non-flight-critical system is one thing. This is another.
 

TXFlyGuy

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One inop system means you're just another inop system from two and, if you took off with one, it means you're going to find the second in-flight. Whatever that second one might be, the first may limit your options in dealing with the second in a way that limits your options to go on living.
Thanks for your answer. You just hit the proverbial nail on the head!
The known inop system could easily affect the outcome with a second system failure.
That is the response I was looking for.
 

dwalker

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Depends on the failure mode of the flaps, and the aircraft.

I would fly a Carbon Cub with inop. flaps that do not interfere with other controls, but probably not some other airplanes.


BJC

I like this answer. If I was supremely proficient with that specific aircraft and the major but not critical flight system... then maybe?

I have been thinking a lot about this since my Dragonfly will most likely be in phase one about this time next summer. Since I am not an experienced test pilot, and am not a high time super pilot, for me the answer would be absolutely be nope. Literally every system will have to check out within limits or I am not going to attempt to fly it. Back up fuel pump not working? Not leaving the ground. Weird reading on the tach or intermittent electronic interference? Not leaving the ground. Speedbrake (no flaps) not locking into place or actuator sounds like its working hard to retract? No go.

For me, the non-professional homebuilder low time guy, I honestly cannot think of anything I personally would fly with any sort of squawk in a flight system.

Now, if I were a professional test pilot, with hi time in type, and I knew there was un-corrected issue with a plane, I cannot think of any reason why I would fly the plane. First, I am in theory getting paid to do it, and there is no reason not to demand the aircraft be in fully functional condition.
Second, it is not my aircraft, but the second I commit to flying an aircraft I know has even a single item INOP, it is on me 100% to bring that aircraft back in one piece.
Third, and again in theory, I have a high standard of what passes for "flight ready". As a test pilot I should have a set and inflexible test protocol in place for my personal safety, the safety of the aircraft, as well as to make professional evaluations of the aircraft. Launching with known issues invalidates any such data.
 

TXFlyGuy

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If the hypothetical test pilot decided to take an airplane airborne with known multiple systems either inop, or seriously degraded in performance, it could fall under FAR 91.13 -

91.13-Careless or reckless operation.
(a) Aircraft operations for the purpose of air navigation. No person may operate an aircraft in a careless or reckless manner so as to endanger the life or property of another.

Like my friend says, this is the "catch all" for when the FAA can't nail you on anything else.
 

dwalker

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If the hypothetical test pilot decided to take an airplane airborne with known multiple systems either inop, or seriously degraded in performance, it could fall under FAR 91.13 -

91.13-Careless or reckless operation.
(a) Aircraft operations for the purpose of air navigation. No person may operate an aircraft in a careless or reckless manner so as to endanger the life or property of another.

Like my friend says, this is the "catch all" for when the FAA can't nail you on anything else.
I would think so. I guess an argument could be made that as a test pilot- which is what anyone flying in phase 1 IS- that pilot makes the decision to proceed with a flight knowing there are known and documented issues, that is "thier call" and could not be considered as "reckless".

I would disagree with that argument, but it would be made.
 

D Hillberg

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Test flown Helicopters that had bad control harmony that required rework, Flown others that needed fuel system and oil systems that needed redesign. and others that were a waste of time. [Ideas gone way over the edge]

Flying with a known defect in a system is not a grounding situation even with Part 91 or 135 operations -
Defered maintenance
It's what risk management is about, Testing with known failure modes will establish how well or badly the machine reacts in a controlled environment . . . Establishing procedures - two rudders? two elevators? two ailerons? two flaps?
 

Kiwi303

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Phase 1? No, not personally, others may differ.

But at phase 1 you're still poking and prodding and observing how things work... Now something has stopped working, which for me at least would mean a decent investigation of WHY that system is inop, locate the problem, determine the best means of A) fixing the existing problem and B) ensuring said problem does not happen again.

AFTER it has been sorted is when to go flying again.


Even later after it's passed, and been flying for a while, Flaps are a control system, if a linkage or other part of the flaps system is broken, that's a red flag to thoroughly strip and check the other flight control systems, if your flaps are gone, how can you be sure your elevators or rudder etc aren't going to go shortly too? At which point while everything is opened up as you hunt for anything that may have been hidden from preflights/checks, you may as well fix the flaps while you're in there.



Artificial Horizon et al is a different matter... just fly eyeball on the horizon on a sunny day VFR...
 

TXFlyGuy

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There are items that can be MEL'd...Minimum Equipment List. Allowing you to fly with certain items inop. In the Part 121 world, flight controls do not come under this category.
 

dwalker

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Test flown Helicopters that had bad control harmony that required rework, Flown others that needed fuel system and oil systems that needed redesign. and others that were a waste of time. [Ideas gone way over the edge]

Flying with a known defect in a system is not a grounding situation even with Part 91 or 135 operations -
Defered maintenance
It's what risk management is about, Testing with known failure modes will establish how well or badly the machine reacts in a controlled environment . . . Establishing procedures - two rudders? two elevators? two ailerons? two flaps?
I really want to agree with you, because testing with things that do not work is how you establish minimums..

But I have to say that would exceed the envelope of Phase 1 flight testing. In Phase 1, as has been very, repeatedly, and thoroughly bashed into my brain, the airplane is expected to be as new, with all systems working. Phase 1 is to make sure the aircraft you just assembled is in fact a functioning aircraft and not a pile of parts slapdashed together.

At least that is my understanding of Phase1.

Now, I can 100% see that if you are developing a system, troubleshooting, etc. the need for a test pilot to to take a known sound aircraft with a known issue up to evaluate the why and how and path to fixing it, but again that seems to exceed the envelope of Phase 1 flight.
 

TFF

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I think in general the answer is no. If there were provisions to lock the flaps mechanically, maybe for a ferry flight. It’s really got to be best option though.

Having been a 121 and 135 mechanic. I have gone to outstations to lock flaps up or pin landing gear down for ferry flights. My favorite is I use to work with some Russians. I was working on a spoiler defer and one of the Russians said on a TU-xxx you unbolted the spoiler and threw it in the cargo and flew around with a big hole in your wing.
 

cvairwerks

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Until NoFlaps performance numbers have been established, not a snowballs chance, unless flying off of Edwards, Groom Lake or other similar facilities.
 

TXFlyGuy

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For the sake of discussion, lets just say this is a high performance aircraft. Wing loading similar to a Beech Bonanza.

I agree with the above..."not a snowball's chance".

But even having a long runway is no promise of a good outcome. Long being defined as 6,000 feet or longer.
 
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