Continuing a Flight with a failure?

[Kengineer-130]

Just for a bit of a discussion, how many of you would continue a flight with a failure that meant you could not operate a major item? On another forum, one chap posted up this, talking about qualifying cross country flights :

"Mine was Sywell, Cambridge, Leicester, Sywell. Remember taxiing out behind a C130 from Marshall's thinking "Oh f.ck what am I doing here" LOL
Took off and then couldn't get the flaps up... Then, rather than abort, flew the rest at VFE."

Now, as a low hours (96hrs) PPL, and a professional aircraft engineer, this strikes me as a fairly bad idea, not so much in the flying with the flaps deployed for an extended period, as of course they are designed to be used up to VFE, but insomuch as that losing control of a major control surface with no indication as to why would be worring to me, and continuing a lengthy flight is a bit odd, when the option to land back immediatly and rectify the problem is available?

[fwjc]

If nothing else, it's going to muck up the calculations since the cruise airspeed will be reduced, plus the extra drag will increase fuel burn. Both of these will increase the overall fuel required, which, depending on the aircraft might lead to a marginal situation.

Best to land back as a precaution, take a proper look at the aircraft, call the school and take their advice if it can't be fixed.

[fernytickles]

Flying at VFE? Good for hour building.... ;)

But that's about all. RTB would make more sense to me, depending on the issue. Or fly to the nearest maintenance base/longest runway, again, depending on the issue.

[Genghis the Engineer]

It depends upon what's failed, and where I'm going.

20 miles with flaps stuck down, I'd land at whichever had the best maintenance facilities. Flaps stuck up? - I'd do the flight in most cases, but certainly favour landing where I could get maintenance support.

Radio failure? Depends where I'm flying (through and to), but I'd not cancel many intra-national flights for a radio failure. International I have done, and would do again.

Primary controls (aileron, rudder, elevator), any restriction I'm landing as soon as possible.

Trimmer? Depends what trimmed and how badly / in what position it failed.

Doors and windows? Depends?

G

[thing]

Sywell Cambridge Leicester Sywell is never 150 miles is it?

Edit: Just checked on Skydemon, it's 107 miles. Bit odd.

[bingofuel]

One of the taught techniques for poor weather is 'slow, safe cruise' which is a medium flap setting and a reduced speed. The slower speed gives you more time to see and react to what is ahead, and the flap deployment will give you a greater margin over the stall, and give a lower nose attitude improving forward visibility a the lower speed.
So all you did was fly your leg in a slow safe cruise configuration. However I would suggest that flying at say 10 kts below Vfe would be kinder to the flap attachments and linkages.


Re the 150 mile , comment, I think it refers to the comment re a qualifying cross country which should be 150 nm and 2 intermediate landings

[foxmoth]

Sywell Cambridge Leicester Sywell is never 150 miles is it?

Edit: Just checked on Skydemon, it's 107 miles. Bit odd.

Probably just felt longer - not sure where you got the 150 miles from, cant see it on this thread?? Also, he says Remember taxiing out behind a C130 from Marshall's so from that the Sywell - Cambridge leg is not part of the bit done flap down.

As far as continuing with a failure goes, my view is much the same as Genghis, though we are both pretty experienced and some failures a pilot with low hours might get worried over we might be just considering a minor annoyance.:hmm:
I would also go with BFs suggestion of Vfe -10, at Vfe it only needs a lapse in concentration or an unexpected updraft and you are at Vfe +10.:ok:

Edited to say
Re the 150 mile , comment, I think it refers to the comment re a qualifying cross country which should be 150 nm and 2 intermediate landings,
Of course, should have picked up on that:\:\

[mcgoo]

Probably just felt longer - not sure where you got the 150 miles from, cant see it on this thread??

In the OP, the route is supposed to be a QXC, which is 150nm minimum.

[Kengineer-130]

Bingo,
The point I was making is that flying with an aircraft in a selected configuration is fine, flying it in a configuration due to an unknown failure over an extended time, with the option to easily RTB is perhaps not the best display of airmanship?

[Halfbaked_Boy]

thing,

Sywell Cambridge Leicester Sywell is never 150 miles is it?

Edit: Just checked on Skydemon, it's 107 miles. Bit odd.

I flew the same route doing my QXC - the leg from Leicester to Sywell is normally via DTY, which still gives only about 127 NM. Probs another via in there somewhere :ok:

edit: I lied, mine was Tollerton, not Leicester!

[Gertrude the Wombat]

flaps stuck down, I'd land at whichever had the best maintenance facilities
Which, having just taken off from Cambridge, would be to land back at Cambridge.

[bingofuel]

Point taken Kengineer. Probably depends on how well you know the aircraft. Is it an electrical failure on say a cessna with little chance of the flaps moving on their own accord, or could it be a mechanical fault with the chance of an uncommanded flap retraction?

Either way, I think I would do some fault diagnosis and handling tests at altitude before an immediate return as the last thing you want would be an unexpected , uncommanded flap retraction at 50 ft on the approach!

[peterh337]

In the case of the flaps example, the answer would depend on my view of possible assymetric flap situation, which would probably be lethal.

On the TB20, it "cannot" happen because there is a shaft that joins the two together.

On a short flight, say 200nm, and at low altitudes, say below FL100, I would probably fly on, but it does depend on various factors. If it was just a fun flight then I would return and get it fixed at the convenient place I am based at. It would probably be a flap motor / relay fault which is fairly easy to fix. If it looked more sinister I would return immediately, without touching the flaps.

[achimha]

For me this would be a pure time/fuel consumption matter. There is no safety aspect to this depending on how the flap mechanism works.

I do not check flaps during preflight on my Cessna as I know that in case they don't work, I would do the flight anyway and if they fail during approach, I would just land without (which I practice regularly). The flaps are mechanically linked so asymmetric flap deployment is not an issue.

My old plane is a C172M with 40° flaps. I was always concerned about having to go around and then flaps failing to retract. Depending on the weather and weight, a C172 is impossible to keep in the air with 40°. I guess that was one of the reasons why Cessna limited the flaps to 30° in the C172N and newer. I never used the 40° after having tried to go around with flaps fully retracted.

[Pilot DAR]

Depending on the weather and weight, a C172 is impossible to keep in the air with 40°

I disagree. Unless the aircraft is being opereated with a baffed out engine, or overweight, It will fly and climb in accordance with the design requirements to do so, which include a "balked landing" full flap climb. I have flown several Cessnas to maintenance with flaps fully or partly extended, with no problems.

[foxmoth]

On the TB20, it "cannot" happen because there is a shaft that joins the two together.

Until the shaft breaks! Do not believe ANY statement that it cannot happen! All you need is corrosion in the right place and then the extra strain from another failure and the impossible happens!

C172 certainly WILL fly with Flap 40, the big problem with Cessna Flap 40 is the push needed on a GA, but once you have the trim sorted it is quite flyable.

[Captain Smithy]

I'd consider stuck flaps to be a fairly major thing, I'd be more worried about the potential cause being some sort of control restriction somewhere in the linkage e.g. a spanner or something lodged somewhere that could migrate elsewhere and cause further grief to the primary controls, so I'd probably RTB. If found before takeoff I'd definately not bother flying and get it checked pronto.

Continuing flight with the flaps stuck extended seems pointless to me - so much extra drag, fuel burn and time, plus the above concerns. But each to his own judgment I suppose.

[mary meagher]

Rented a 172 to fly, in stages, from St. Petersburg Florida to Austin Texas.
First of all, we couldn't get one of the doors to close. Struggled and struggled, finally got it to stay shut, and I said from now on we'll pretend its a Piper, still got one door serviceable!. Refueled at Talahassee, carried on to Baton Rouge Louisiana. Enormous runway. ATC requested us to expedite, as we are number one and a 737 is number two behind us. So I skedaddled down the approach, and over the numbers, moved the electric flap lever down.

Nothing happened. So I said, O ****, and continued the landing with no flaps, which was no big deal. Except you should never say the O.S. word with a nervous passenger; he was gripping the armrest whiteknuckled thinking that these are the usual last words of a pilot in extremis...

Nobody available in Baton Rouge to fix the flaps, so what the heck, carried on to Conroe Texas, abeam Houston. By this time, benign IMC, flying in the clear smooth space between a cloud sandwich. And on approach, realised one of the two VOR/DME was up the swannee....Houston vectored me down to 800 feet and we broke cloud. My passenger went for a coffee, I went to talk to Flight Service, who said that Austin weather was terrible and getting worse. So I went to my passenger and said "Very sorry, we'll either have to rent a car, or stay here until the weather improves, which won't be until tomorrow at best." Said he, "Can't you get a second opinion?"......! ! !

We rented a car.

[The500man]

I wouldn't have continued with stuck flaps personally, although I can see the temptation to take the aircraft home with a flyable problem so it can be fixed where it lives. I suppose you only need to consider whether flaps stuck in the take off position will hinder your planned arrival at your destination (short field perhaps), and whether the failure is an indication of another problem or if it will seriously gimp your cruise.

I've only experienced a failed vacuum pump in VMC, a radio which wouldn't transmit, and a magnetto problem. I chose not to continue with any of those problems although the first two were not really serious. I generally wouldn't continue a non-essential flight with a technical problem. I think you should be very respectful of gravity!

[Big Pistons Forever]

My 02 cents

It is always better being on the ground wishing you were in the air than being in the air wishing you were on the ground, so if in doubt land at the nearest suitable aerodrome

However the key to dealing with in air malfunctions is solid systems knowledge. A failure of the electric flaps to move in a Cessna is just that an inability to change flap position. It is almost always an electrical issue and does not per se mean that the airworthiness of the aircraft is compromised. The performance will certainly be compromised, however so a decision needs to made as to whether it would be wise to continue the trip.

I once had to deliver a Cessna 421 from Toronto to Vancouver. By the time the aircraft made it to Vancouver I had documented 58 defects. I started out with what was supposed to be a day/night VFR/IFR known icing capable airplane and by the end of the flight was only continuing in day VFR unpressurized flight conditions. There was a lot of things not working but the failures could be ameliorated by changing how/when I flew.

[robin]

We had a trim failure as we launched from a strip. We could have landed straight back but chose to fly home 45 nm away where the maintenance facilities were.

The aircraft was flyable and actually trimmed for the approach but I wouldn't have gone much further

[mrmum]

Sywell Cambridge Leicester Sywell is never 150 miles is it?
Edit: Just checked on Skydemon, it's 107 miles. Bit odd.
The person referred to may of course have been undertaking a course of training for an NPPL - SSEA, rather than a JAA-PPL(A), in which case the described route of 107nm is perfectly acceptable.
NATIONAL PRIVATE PILOT LICENCE
Simple Single-engine Aeroplane (SSEA) Course
COURSE DESCRIPTION
Flight Training
Of the minimum 10 hours solo, a student must complete at least four hours of solo cross country flight, including one cross country of at least 185km (100 nm) in the course of which full stop landings at two aerodromes other than the aerodrome of departure shall be made.

[Captain Smithy]

I always look on it as "do I absolutely desperately need to fly?". The fact is that unless 1) I was stuck in some backwater airstrip out in the wilds of the Arctic/a jungle/desert/wherever and absolutely had to get out, or 2) I had some other pressing life-theratening need to fly, then the answer is "no".

Interesting story mary meagher. I've heard many horror stories about aircraft rental in the states and some of the sheds/deathtraps that are palmed off to unsuspecting hourbuilders and somehow passed as airworthy... :uhoh:

[Fuji Abound]

An interesting question which has caused some debate in the past is continuing flight on one engine in a twin.

It can end up being a hotly debated subject and is a good example of the pros and cons of continuing with any failure which in itself might not be critical.

[david viewing]

Apologies if someone already mentioned this but flap failure in a 172 might be a jammed motor with subsequent fire risk. Personally, I'd land back.

Regarding flying on with trim failure, this (http://en.wikipedia.org/wiki/Alaska_Airlines_Flight_261) makes interesting reading.

[enq]

For me, flaps stuck down also raises the question of how this will affect my ability to cope with an engine failure (or other additional problem).

Deployed flap not only removes significantly one of the most controlled methods of increasing rate of descent at a given airspeed (I find side slipping always takes me by surprise r.o.d. wise) but will give me a glide angle that is steeper & not as familiar from PFLs increasing the undershoot risk.

Similiarly, as well as concern about the cause, other types of failure also need to be thought about in terms of cumulative effect & the individuals ability & confidence in being able to cope with failure 1 + failure 2.

Personally, as I'm sure is the same with most on here, I try & enjoy a type of flying that stretches me but does not leave me feeling vaguely uneasy for the entire flight.

[englishal]

Did the OP check the circuit breaker for the flaps I wonder ?

Depends entirely on the failure. We had a dodgy impulse spring on a mag, but I happily flew it home as I was pretty sure that once started the thing wasn't going to stop. Else it would have meant lots of hassle. I had the AP CB pop a few times on one flight for no apparent reason, no reason to cancel, just hand fly. I had an engine in a twin over mountains develop a misfire. I turned around and went home. Had fuel pressure indication drop to zero in a SEP shortly after take off. I aborted the flight and went to the pub instead after a bit of umming and ahhhing and "it is probably the gauge"ing.

(NB: The gangsters who pretended to be aircraft mechanics at the flying school where I rented the plane dismissed this as a gauge problem after a 10 second inspection. A few days later the engine stopped at the run up with FI and student onboard due to fcuked fuel pump).

[AdamFrisch]

It depends on how well you know the aircraft you fly, as well.

I had a malfunctioning gear light for awhile. I knew the front gear was locked and that the switch had just fallen out of alignment slightly. Once that was repaired (due to a cracked stiffener), all worked fine. Until, it started to go out again. The landing gear also "felt" slightly different, mushier somehow, on landings. I decided to have a look at it and as I landed at my mechanic, the front gear collapsed as they wheeled her into the hangar! Was another major structural crack hidden behind a panel that had not been seen earlier. But I had a feeling something wasn't right this second time around - sometimes they'll give you a hint.

[mary meagher]

Captain Smithy, I can't afford to rent airplanes in the UK! so had to rent a shed in the USA, but certainly true you must beware beware beware!

The stupidest things can go wrong that you might never expect. The most you can hope for is that the engine keeps running, and if its a Lycoming it probably WILL keep running! bless them!

Actually one of my most exciting moments was at Orlando Executive, in a Cessna 152. Now the Cessna is a sturdy aircraft, puts up with all sorts of abuse, neglect and contempt, but it is the nursemaid of many of us starting a flying career. Orlando Executive is quite busy, all circuits and approaches are just underneath all those tourists flying into Disney International.....

I was preflighted, prepared, approved, cleared for takeoff. Throttle moved steadily and strongly forward, the little darling responded by eagerly surging forward, and I and my seat with the classic action/reaction scenario, slid backward and departed the controls! so I aborted the takeoff. Don't do that a lot, but seemed like a good idea. Sat there shaking, obstructing the active runway. Tower enquired snappily "Something the matter, Cessna 43885?" "My seat slid back!" "Expedite your return to base" recommended the tower, so I did.

Its a common fault aparently, and worth checking out, in more than just Cessnas.

[mad_jock]

There was a fatality in the air due to that mary .

And I believe there was an AD to get them all fixed.

[Captain Smithy]

Yep the migrating seat problem was a well-known gotcha in Cessnas of yore and was AD'd, should all be sorted now. I heard that the modern Cessnas have the seat rails from the Caravan which apparently are much beefier.

[Genghis the Engineer]

I've had it once, fortunately I was flying with another pilot, who heard "You have controlllllllll" as I shot towards the back of the aeroplane.

I was once asked as a certifying engineer to approve the design of an aeroplane which had a seat rail design substantially the same as the usual Cessnas. I refused to approve it until they'd added a small cheap mod to put a backup strap along the floor so that once the seat was latched, the pilot could simply tighten the strap up - so if the pins went, the seat was incapable of sliding backwards.

When I explained the Cessna history, and showed that the total parts on the aeroplane would cost about a fiver, the company were quite happy. To date, the aeroplane's never had a problem!

G

[AN2 Driver]

Had the seat problem happen on a Caravelle. Brief pitch up before the PIC released the controls and FO took over. Not fun.

Re flaps,

locked up, I'd fly it home or to the next maintenance if practicable, that is if the maintenance is based on field of the increased runway lenght I'll need. Most SEP's are very easily flyable flaps up.

partially extended such as in take off position it would strongly depend on the distance to fly. 90% of the time it's RTB, if it's a 50 mile leg to homebase where the engineering is, I'd probably go on.

Re RTB:If you're in Italy, think again :E might become expensive. Which might lead someone to NOT RTB and crash. That is why Italy is off my list for now.

[BackPacker]

Just for a bit of a discussion, how many of you would continue a flight with a failure

And to spice things up a little, and going back to the original post, how many instructors would praise a QXC student for bringing an aircraft with U/S flaps back to home base, and how many instructors would get angry at him/her for not landing back at the departure airfield and reporting/discussing the problem by phone?

I'm not an instructor but if I were I would probably do the latter.

It's one thing to carefully consider the consequences, such as the additional fuel burn at lower speed/high drag, and the possibility of damage to flap attachments & motor, and then make the decision to fly the aircraft to a maintenance base. But it's quite another thing to continue a flight when a problem suddenly appears.

(And I wonder if the student ever consulted the POH to see if it had anything to say about it.)

[mad_jock]

Depends who the student was and there reasoning behind why they did it.

There isn't a right or wrong answer to be honest. Personally I would pull the cb and carry on thinking heap of crap wish it was a tommy.

A 16 year old who couldn't account for themselves would get an earful more to batter some PIC skills into them.

But say a mature student who had at least thought about what was wrong and made an informed decision along with the effects of the condition would get debriefed and thats about it.

Its quite a good exercise to be honest to stimulate the student to think about what if's. Perfect for a bad wx day sitting in the briefing room.

[n5296s]

The trouble is it's hard to think of and through all the possible failure modes while in the air.

A few years back I did a very long trip. On the outward leg, Palo Alto to Denver, I flew high (FL200) and noticed that I had just a little bit less boost than I expected - the throttle was pushed in a little further. (On the TR182 the second half of the throttle movement is actually gradually closing the wastegate).

I didn't worry about it, I figured the rather complicated linkage must be out of adjustment. On the ground in Denver I took the cowling off, but the linkage is both complicated and well hidden and I couldn't see anything obviously wrong.

The journey home was in several stages. At each stage I was getting just a little less boost. Finally in Lancaster (fuel/lunch stop) I had a mechanic take a look at it. Ouch! It had nothing to do with the linkage. The locknut on the turbo impeller had come off and was gradually chewing up the aluminium impeller. By now there was very little left.

Had I known that, I would certainly not have been flying over the Rockies at 2000' AGL!

[Kengineer-130]

N5296s,

That is exactly the sort of failure mode I am talking about. An excellent example of a seemingly innocuous fault that later manifests itself as somthing far more sinister!

The worst fault I had to deal with inflight was a rough running engine at night. I had been to Flagler county airport along with 2 other pilots, each of us in a c150. We landed after a short flight from ormond beach, and stopped for tea at hijackers cafe ( I can highly reccomend the chicken kabobs!:ok:).. After which, we decided to fly up the coast to St Augustine, about a 25 min flight.

During the Pre-take off power check, I got rough running on the right mag, so following the training I had, I did a slightly lean power run to clear the fouled plug, which worked a treat, and restored full power & smooth running.

We took off, and about 5 mins into the leg, my engine started running rough again, which for a newly qualified ppl at night, is quite worrying! Switching to the left only mag cured it, but I immediatly diverted back to Ormond beach, and landed without incident.

In the morning, I spoke to the mechanic, who said it was simply a worn plug, but to me it made sense to return to base rarther than press on over dark, unfamiliar terrain with no real need to continue the flight, which was simply hour building...

[mad_jock]

There is a difference between having a fault with you one and only power plant and having the flaps refuse to come up.

Coming home with the flaps isolated via pulling the CB is fair game in my book.

Doing anything with a rough running or "something not right" with your only engine is a completely different kettle of fish.

[Pilot DAR]

I was flying with my wife in the mighty C-150, down through Virginia, many years ago. On the radio, I heard a Coast Guard C-130 Hercules reporting an engine failure, while they were returning to their base. This did not seem too concerning to anyone. Then their base went below limits, so they would divert to Roanoke - Hey, that's where we were headed!

As we both worked our way toward the same airport, the Herc pilot's voice took a whole new tone of alarm, he declared an emergency, reporting he'd just lost a second engine. He sounded really scared on the radio. A lot of paniced chatter happened over the following five or so minutes....

He landed a minute before me, and the reason for his alarm became obvious to me as he taxiied across in front of me....

It appears that number 2 would not feather after it quit!

(Try as I might, Photobucket refuses to resize this photo - sorry!)

http://i381.photobucket.com/albums/oo252/PilotDAR/Aircraft/roanoakherc1.jpg

[peterh337]

Nasty... I wonder what the cause was.

An excellent example of a seemingly innocuous fault that later manifests itself as something far more sinister!

Exactly, which is why I was suprised that flying a 747 from the USA to the UK with one engine having shredded itself during takeoff was a procedure (a) approved by the UK CAA and (b) one which the PIC was happy with.

Perhaps he would have been sacked if he failed to comply with the approved company procedure?

[Kengineer-130]

If the 747 incident you are talking about is the one where the engine surged on take off, and was subsequently shutdown, it is a different scenario.

An engine surge is generally not a catastrophic failure, it is a breakdown of airflow through the engine, so the shut down as I recall was precautionary, as the crew were unable to clear the surge.

The other point to consider is that a fully loaded, fuelled 747 will be way over its maximum landing weight, so to RTB would mean either burning off fuel, or dumping it to obtain a suitable landing weight. As it has plenty of power on two engines, continuing on 3 would be more than acceptable, albeit at probably a reduced cruise altitude. The aircraft was never more than 45-60 mins away from a suitable diversion, so from my limited commercial knowledge, it was a safe & prudent decision to carry on with the flight.

ETOPs can now run to 180mins for a twin engined aircraft, which does personally make me slighty nervous, but these decisions are not made on a whim, and the engines & airframes today from an engineers point of view are reliable to the point of boredom :ok: