Pre-flight Checks... any problems found?
 

As a low hours PPL student I am now doing some of the preflight checks etc....

My Instructor has told me a few of the problems he has encountered in his years of flying...

What problems you have found during your checks?

Groundcrew gloves in engine intakes, zeuss fasteners undone, crack on stbd undercarriage leg locking ring, knackered tyres! (not all at the same time thankfully). It's worth taking your time over.

Standby for the rush!

PingDit
:bored:

Another student
 

Student learning on a Cessna 152

I've had rough running on one set of cylinders when doing the mag check, had to abandoned the flight for the day.

Common problem of low volt light coming on the ground, switched the master switch off and on to get rid of that.

On take off had a door come open.

Look out for loose screws securing the rocker box covers on Lycomings. Worth giving them a tweak with the plain screwdriver end of your fuel tester when doing the check A. (But try not to burr the screw slot!).
Aileron hinge cracked.
Damaged aileron caused by mishandling on the ground.
Missing split pin in main undercarriage scissor links (post maintenance).
Loose hot air box.
Primer line fractured just below the nut securing the line to the cylinder.
All on a PA28-140.
Have a go at the walk - around check competitions that are held at events like the PFA rally. You'll be surprised at how many faults we miss........

Too much fuel in the aircraft (that's a real pain to sort!)

Thanks for the input so far...

Hope I have started an interesting thread!

Had a fuel drain absolutely full of water on a club aircraft before now (later found out it had been grounded at another airfield for almost a week due mag failure). Drained a couple of litres from each tank, giving the wings a shake to dislodge any trapped pockets, was all looking good before long.

Started spluttering like chuff at 500ft on the climb-out. Had enough alt to do a turn-back and landed downwind (managed not to soil myself). Turned out fuel-filter was full of it, which no amount of fuel draining would cure.

Mr_B - rough mags are quite commonly down to mucky plugs. Can usually be cleared by agressive leaning and a decent ground run, then checking the mags again, usually clears it.

I've strained out water from fuel tanks - (not caused by condensation)- a leaky seal at the filler end on one wing was permitting ingress.

Flat tailwheel tyre when I flew a taildragger with an inflatable tailwheel.

Blown fuse in R22 BII - discovered when trying to engage clutch.

Various blown bulbs - particularly Robinson landing lights.

Dent in cowling discovered immediately after release of R44 from workshop I once used - no responsibility admitted by engineering so I never went back and now warn others off. New workshop ensures my aircraft is clean and polished when I go to collect it and is serviced by people who seem to take pride in what they do.

Cockpit full of grass - thoughtful mower man had cut grass next to adjacent cockpit vent.

Aircraft covered in grass - the day after I have cleaned and polished it and the thoughtful mower man had once again struck.

Hole in tail rotor blade - Never properly resolved cause for this - maybe a stone, maybe other ground equipment. Grounded me for a while.:(

IMHO the best opportunity to discover problems is when you are washing the aircraft. No dent or ding will be able to hide.


So it's worth doing, it gets quicker but no less thorough with time and familiarity.

SB

I've found quite a number of faults over the years, all pretty mundane and what you would expect from time to time though.

Squashed oleos (club)
Dings in prop that needed filing out (group_
Faulty stall warners (club)
Faulty pitot heaters (club)
Faulty lights (club and group)
Loose screws on cowling (club)
Oil leak in engine bay (group)
Bald tires (group)
Very worn disc pads (club)
Weeping brake calipers (club)
Blocked pitot (club)
Seized brake (group)
Tripping alternator (group)
Failed Turn Coordinator (club)
Detached dorsal faring (group)
Water in fuel (club)
Plenty of abandoned pens and pencils happily rolling around the floor (club)

I think that's it.

I was a student that flew 4 or 5 different C152s at the school... all of them had faults. 2 of them always had a rough running engine on the left mag and I was always told that it was fine (in fact, I was told I was fine for every fault I found).

- Low voltage light.
- Doors open in flight, even after checking them properly.
- Window locks broken, so I couldn't close them.
- Mixture control would always pop out. :ooh:
- Parking breaks didn't work.
- DI would never be aligned with compass for more than 30 secs.
- Radios never switched off.
- Dents all over the wings. :confused:
- Cracks in the fuselage.
- For one aircraft, I'm not sure if the carb heat worked (engine RPM never dropped - but I was told that it was working).

I guess that's normal. The C152s still flew.

Leaking compass - almost completely empty. :eek:

Vacuum failure - HSI failed, caught while doing taxi checks, so flight aborted.

SD

Screw on Spinner
Water in tanks
Incredable low oil
Low voltage warning light
When helping with some maintenence (PFA) we almost missed off some lock wiring till I spotted it so always work in pairs likelyhood of both missing it small
Dave

Seat belts fitted wrong way round in a 172 immediately after an annual! This made it impossible to fit the shoulder straps - I guess the test pilot didn't use them!!!

Walkaround:

Ice on wings (instructor: "well done for spotting that, let's go flying anyway")

Not enough oil (more than once, fixed by a man with an oil can)

Squeaky aileron hinges (fixed by a man with a different oil can)

U/S beacon (instructor: "do the strobes work? OK, I suggest you notice the beacon failure when you come back from flying")

Earthing braid on elevator almost worn through, only a couple of strands left (instructor: "it's OK for today, but we'll certainly put this in the book for the next check")

Water in fuel (only found once, but took a bit of clearing)

Fuel quantity wasn't what I expected from the paperwork (in both directions, including once so empty that the previous pilot was bloody lucky to land it normally)

U/S handbrake (but if I'd been properly awake I'd have known that before getting into the aircraft, as it was properly documented in the paperwork)

After starting:

Front suspension bottoming out (rejected aircraft, took a different one)

Failed power check (instructor showed me how to burn the crud off the plugs)

After take-off:

Oil pressure well above upper red line (instructor took control, flew circuit, landed, gave aircraft to engineers; turned out to be an instrument error mis-reporting a healthy engine) (neither of us noticed this during power checks or on the runway :O)

Seems to be a standard feature of 152s.

Happened to me on my first ever flight with a passenger.

But I'd seen it before, so calmly reached over and shut the door, explaining to the passenger that it's the seat belt that's keeping him in the aircraft, all the door does is keep the draught off.

The worst - trim connected the wrong way prior to a test flight! The same a/c had the pitot/static mixed up - noticed no ASI on take-off roll.

In the last few months.....

Broken exhaust joint
Broken exhaust stud

loose spats

blocked pitot

tailspring on point of collapsing


On my own a/c I notice most of the defects when I wash/polish it. The w/round then becomes more of a confirmation of serviceability than a defect spotting exercise.

How do you pick up wrongly connected trim? You've got me worried now. You can't really see the trimtab from the cockpit in a PA28...

Tim

Some things I have found so far during preflights (PA-38):-

-U/S Landing Light
-Loose starboard strobe light
-Grit in fuel :eek:
-Small dent in metalwork just below the windshield on port side... caused by the door being snatched from your grasp on a windy day... oops :\

Also had a funny one when I tried straining the fuel bowl and no fuel came out.

Me: "Er, there's no fuel coming out of the drain."
Instructor: "That's because the fuel selector is off." :ugh::rolleyes:

D'oh!

And you willingly strapped this thing on your back ? :uhoh::eek::eek:

Braver man than me, Gungadin ....

FF :ok:

The carb heat came off in my hand during initial start-up checks once - soooo irritating as it was my first flight after a long spell of bad weather and its the closest I've come to tears since the budgie died :{

I've found quite a few things, especially on spamcans I used to rent, but the only ones that were dangerous were (a) bare landing light wires hanging around the engine compartment (Tomahawk) which could have shorted to the airframe resulting in a fuel fire/explosion (which the instructor wasn't bothered about and simply told me to not use the landing light - I walked out of the school after that**) and (b) two occassions where the tanks were found totally empty and wildly differing from the fuel in the tech log, either due to overnight fuel theft or due to previous pilot(s) having got very very lucky... Consequently, the subsequent G-OMAR accident was no suprise to me at all.

** One wonders what sort of stuff would be found in flying school spamcans on which the preflight does not include looking under the engine covers (i.e. most of them).

I also once found a slightly flat tyre - this needs to be taken seriously because if it is a recent slow puncture, the tyre could be totally deflated by the time one lands. In this case, the cause was a tiny puncture in the side of both the tyre and the inner tube; god knows how that happened...

WRT your comment about looking under the covers IO, our club checklist includes a check of the engine compartment - to check oil and brake fluid levels, and for any birds' nests that may have "appeared" overnight... also a good idea to check that the HT leads are all in place, no leaks etc.

Would be very worried about any club/school/pilot that does not check the engine bay before flight. Think I'd be staying on the ground.

Interesting story about the Tomahawk, IO. Think I would've walked out too.

My first ever flying lesson. My and my instructor were ferried to a distant airfield to pick up a plane which had been painted. The flight back would be my first lesson. After doing their (shoddy) paint job, the painters had removed all masking tape. Except for the pitot/static mast (PA-28).

Oh, and this was a short grass strip and the temperature was already above 30C when we discovered this. It would not have been pretty.

Let's not forget aircraft still tied down.
Hat, coat, taxi....

How did I spot the elevator trim was working in the wrong sense?

Standing outside the aircraft facing backwards - right hand on the trimmer, left hand on the stick. The bottom wire had been connected to the top and vicky vercky, the trimmer did not feel as smooth as normal - but I doubt that if I hadn't not noticed the wrong movement I would not have discovered it until I retrimmed in flight - normally early on the climb out!

I cannot see a PA-28 trimmer when I am in the seat either. So I exercise it by reaching inside whilst in a position where I CAN see that it is working, symettrical etc. Same goes for anything on any other plane where I cannot see it from the seat and play with it at the same time.

Oh and I always check the "sense" of travel as well as for full unimpeded travel, as I do for the elevators and ailerons.

Since I once found an aeroplane with almost no fuel on one side and half a tank on the other .. I have decided to treat any aeroplane is if it has been last used by somebody trying to catch me out or do me in.

DGG

interesting topic, especially good reading for students!
In 5 years of light aviation flying I had the following:
-found loose oil filler cap (the previous pilot had a lot of luck I guess) (PA18)
-no rpm drop during testing of carb heat (found to be the connection rod between engine and lever loose under the hood) (PA18)
-during mag check found engine rpm varying rapidly between 1000 and 1700 rpm on one magneto. (PA18)
- found one main tyre partly deflated (c152)
-also had the pax door opening on take off, since then is an important point on my preflight
-flat battery (prop manual crancking, on PA18)
-spring of tailwheel not connected to rudder (PA18)
-full fuel tanks found on a C152 with long range tanks, =overweight with a passenger!
-front window full of bugs, hard to fly VFR
-of course the occasional low oil
- I once saw a C152 taxiing with the nose gear tow bar connected.

As mechanic on the big stuff, I have to admit these planes fly with a LOT of known problems, and nearly every flight brings up some things that are not right.

Sent out on GFT to pre-flight a C152 that had had its 50 hour check about a week earlier, but had flown about 20 dual hours in the meantime. Checked the prop and got down low to check the air intake (below the landing light) and found out it had been installed upside down and deformed itself and the cowling. My GFT was postponed until another aircraft was available, but got me a shed load of brownie points with the examiner!

Not so much a pre-flight check, but pre-flight nevertheless, on my the final leg of my qualifying cross country when taking off on Shoreham's bouncy grass I discovered the spring holding the seat lock in place had failed. Hit a bump, back goes seat as does the control column and throttle! Luckily I had just enough flying speed and arms like a gorilla so I was about able to sort myself out. I hate to think what may have happened if I was slower/less monkeylike.

Gareth.

Only once have I refused to fly and that was a rented C172.
All was ok until I got in. The pilot seat then collapsed back and I could see light coming from a hole between the rudder pedals. :hmm:

All sorts of FOD, like pens, scrap paper, screwdrivers, screws, a bread knive, washers, and a three weeks old slice of bread. With cheese.

Loose radio, ready to slide out of the panel at 15° pitch attitude.

The usual "only happened yesterday" dents and scratches.

And the scariest: two (!!!) cracks in an engine mount.

I've found those in the PA18 as well, on top of that an engine that would not produce more than 2000rpm in level flight (not really a pre-flight discovery). Mags left on, I once found a PA28 with almost no fuel in one tank- he must have been minutes away from fuel starvation. Water in the fuel is the most common one, often in the tanks it's just condensation but if its in the under engine drain it could mean trouble. General load of rubbish in the cockpit as well.

One of my mates thought it would be a bit of a giggle if he sent a student out to pre-flight a PA28 which was missing the propeller. The aircraft had suffered a prop-strike a few days before, the damaged propeller had been removed and the aircraft returned to the line whilst they waited for the new propeller to arrive.

The gag almost back-fired. The student never noticed the missing propeller.:ugh: The instructor found himself running out to the aircraft at high speed to prevent the student from starting the engine. Without the load of the propeller, he could have over-reved the engine.

Sometimes it's easy to find insignificant little snags (like missing screws) than it is to find bigger important ones.

Pilot of 182RG complained that he couldn't get the required RPM in flight.

It appeared that the engine cowling was fouling the prop control. Adjusted ground run satis.

Pilot came back with same problem once airborne.

While discussing it he mentioned that he had been getting bits in his water drain from the right tank, but not the left for some time.

Investigation lead to a roll of masking tape swimming in the right tank minus all of its adhesive!!!!!!!!!!!

The adhesive was all through the fuel system and was partially blocking the fuel filter leading to the RPM loss.

Lucky man as he regularly flew it over the Alps.

An interesting one on my Tipsy Trainer at Goodwood last weekend.

Discovered two of the bolts on the tailwheel mounting bracket had loosened off. A deckchair from the adjacent viewing area made a suitable trestle while we lifted the tail for the appropriate repairs - much to the amusement of the spectators!