Pilots say they’re being blamed for plane crashes that aren’t their fault

[BJC]

You can, and she probably won't show up for the court date. That is cool because a default judgement will-- if not immediately then eventually-- be entered in your favor. But there is the small issue of enforcing the monetary judgement after you win...

Yup, and then, she will be angry with you, and will find a way to get even.


BJC

 

[skydawg]

Our c172 burns ethanol car gas and up to recently was hangered. Ethanol has a way of absorbing water vapor as well as any precipitation that sneaks in, so water concerns are amplified with ethanol. So I replaced the cap and sender gaskets as it's rainy season

We did a lot of testing with ethanol issues early on and it's no big issue if you follow normal practices, but I would reiterate what was mentioned above about the fuel source......real important that fuel comes from a fresh and reliable source.

Besides fresh suppliers being less likely to have water in the first place, ethanol evaporates more rapidly than lead (both are used to increase octane), so old fuel can degrade to octane levels below engine needs and cause early detonation even with water contamination. Not really a problem if stored right for most. I like to wait a couple of hours after fueling before draining samples before flying to give new contaminates time to collect at tanks bottom.

Our EFI system has redundant fuel delivery system with 2 pumps, filters, pres regulators so should have good amount of time on backup system if main system gets fowled. Used to get contaminated fuel a lot when in Mexico which were self inflicted problems. I hear there are some water absorbing/filtering nozzles attachments that might help.

 

[Bill-Higdon]

How did you know where you picked up the water?

The rest of the story it was a flying club plane a member had flow it the previous day & returned late at night from Wendover. He should have fueled up before he left Wendover, when he landed at Ogden he was real close to running on fumes. The FBO's were closed for the night so I had to put almost of a full load of fuel on board before I could depart. It was in the dry part of the summer, and when they checked the truck after my issue was reported they found a lot of water. Also that FBO was known for being how would you say some one you couldn't trust

 

[Appowner]

Who's fault?

Unfortunately for a variety of reasons the deck is stacked against whoever has their hands on the yoke at the time of the event. The PIC has either failed to check something, notice something or learn something. Being the one who had the last opportunity to prevent the event, they are declared guilty by the arm chair experts of the world. Flawed design, construction or maintenance are secondary if for no other reason that those are usually backed by enough money to say so. Call it human nature.

A sad fact of life indeed and one I don't see us ever changing as it would probably require a level of mass maturity this nation will probably never see. Americans simply do not like to accept responsibility. Especially when involved in something bad happening.

Unable to fly full size anymore I fly RC models exclusively now. And have for some 55 years. You should hear the excuses at a RC field when a model goes down. The radios get the majority of the blame (I charged it three weeks ago!) with the engines following close behind. The fact that the owner over leaned the engine in that desperate grasp for a few more RPM has nothing to do with it. Even once saw a fellow blame a tree for being where it was, having reached up and grabbed his model while on base leg. A tree that person had successfully navigated over many times before. Must have been a sudden growth spurt....

I have had maybe 100 crashes I've walked away from. They were all my fault for one reason or another. Mostly what I'd call dumb thumbs (thumbs run the joy sticks). A servo wire breaks under tension. Should have been longer. I knew it, so why didn't I? A wing shifts and falls off. Only had six rubber bands with me that day. A 9G turn didn't help either. But the best was when I stood behind my Nieuport 17 as it took off. Man that paint job on the top looked nice. Never dawned on me the model was climbing out at too steep an angle. And even when it stalled at some 15-20 feet, snapped and spun in, I remained dumbfounded as to the cause for some time. But again, it was my fault. The PIC being stupid, stupid, stupid! Again!

 

[BJC]

A sad fact of life indeed and one I don't see us ever changing as it would probably require a level of mass maturity this nation will probably never see. Americans simply do not like to accept responsibility.

Yes, sad, because the lack of accepting - taking might be a better word - personal responsibility is the first step down a slippery path that, ultimately, will cost us our freedom and the opportunity to fly.


BJC

 

[Dan Thomas]

Ever wonder why there are so many "low point" drains on a 172S?

I think the older 172 is the worst. But, any wet wing aircraft that gets parked outside, or is infrequently flown probably has trapped water somewhere. Fly to a low enough fuel state and start yanking and banking, you just might find it.

Except that you don't need to get to a low-fuel state. The water isn't floating on top of the gasoline. It's crawling around the bottom of the tank. Any room for the fuel to slosh---meaning less than right full---can pick up that water and move it toward the outlet.

Those many drains on the R & S 172s were necessary because Cessna took the aluminum tanks out of the wings and sealed up the tank bays themselves to form tanks. A true wet-wing aircraft. The stiffeners and ribs in the floors of those bays will trap water, so the drains had to be added at every low point in every possible spot.

The 172R &S fuel bay section of the wing:


Detail A is the tank floor (bottom skin) that goes under Detail B. The front spar (not shown) and rear spar are also part of the tank's walls.

The old design, with the separate tank:



#13 is the tank, held down by two straps.

 

[Dan Thomas]

And is there a 337 for that Cessna fuel drain mod? If not, guess who won't pay if there's an accident, even if it's unrelated to fuel. Not saying it's a bad idea; it (probably) just isn't a legal one.

There's a 1/8" pipe plug in that selector valve, with a small access hole in the skin right below it in any 172 I worked on, and I worked on a lot of them. That plug is supposed to come out every 200 hours according to Cessna's inspection schedules, and accumulated crud flushed out. Yet I found those plugs seized in there because they hadn't been out in 40 years and thousands of hours. In the flight school airplanes I pulled the plugs and installed quick-drains, and the students were shown to sump that spot as well.

The 172R & S came with quick-drains in that spot.

 

[Dan Thomas]

What if you check before flight but your 172 is sitting on just enough of a slope that the water in the tank isn’t gathered around the test drain? That’s the problem as I understand it and the reason Cessna puts 14(?!) drains on the new ones.

Those many drains are due to the tank's different design as I already noted above.

But it seems that so many folks have become ignorant of some basic stuff, like water being heavier than fuel and flowing to the lowest spot in the tank. So in the 172R & S AFMs Cessna had to say this:



A few pages later they say this:



And yet pilots won't do it. They'll just take off and when it quits they'll sue Cessna.

Those airplanes also have header tanks in the floor under the copilot's feet, and a drain valve in it, too. It can trap quite a bit of water.

So many accidents are due to a failure to study that POH/AFM and learn about the airplane. That's not Cessna's fault. It's the lazy pilot's, eager to blame someone else for his shortcomings. It's very difficult to design and build an idiot-proof tank for an airplane, it usually being inside that thin wing, unlike a car's tank. That also makes accurate fuel gauging harder.

 

[Dan Thomas]

Also, planes with bladder-type fuel tanks can develop wrinkles, and said wrinkles can trap water. IIRC, you're supposed to shake the wings during preflight to help chase the water out....

There's an AD on Cessna singles with bladder tanks. Unless their stupid flush-style fuel caps are replaced with the raised caps like you see on 150s and 172s, a placard must be installed on the panel demanding that the pilot push the tail down to the ground (unless it's a 180 or 185, of course) and rock the wings 12" up and down. That is major violence, and the reason that most of them got the conversion kits for the raised caps. The flush caps held water that would seep past the outer and lock stem O-rings and get into the tanks. Of course, shoddy maintenance would let those rings get old and hardened and shrunken and cracked. Cessna's fault? Even though they're on the inspection checklists?

There's another kit to move the sump drain aft and inboard a bit to stretch the wrinkles out of the bladder's floor. Except that old bladders are hardened and those wrinkles quite stiff.

Bladders. Ugh.

Fuel caps are a hassle all across the makes and models. If their gaskets aren't kept soft and fresh, they'll let pounding rain or snowmelt into the tank. The Cessna cap has a small umbrella-style check valve in its underside that is to let air in but not fuel out. It gets old and sags and lets water in. Got to buy a whole new cap to fix that.

 

[Dan Thomas]

The Cessna 150 has a lousy tank. If the nose isn't sitting higher, the water will sit near the fuel outlet instead of at the sump drain. On the ramp, you'll often see this:



That nosegear oleo is almost flat. You can bet that any water in the tank won't be at the sump drain. Owners aren't doing themselves any favors letting things get that way. Low nose tire pressure only adds to the problem.

Now look at this one:



Oleo as it should be.

A 150 is easy to get into position for sumping. A block of wood in front of the nosewheel. Mags off, prop horizontal, grab both blades next to the spinner and lift the nosewheel off and kick the block under the tire. Make sure the airplane is level left-to-right. The blue airplane above is not level left-to-right.

 

[N804RV]

Except that you don't need to get to a low-fuel state. The water isn't floating on top of the gasoline. It's crawling around the bottom of the tank. Any room for the fuel to slosh---meaning less than right full---can pick up that water and move it toward the outlet.

Those many drains on the R & S 172s were necessary because Cessna took the aluminum tanks out of the wings and sealed up the tank bays themselves to form tanks. A true wet-wing aircraft. The stiffeners and ribs in the floors of those bays will trap water, so the drains had to be added at every low point in every possible spot.
...

Kinda my point. Since ANY irregularity in the bottom of the tank can trap water, its necessary to do something to try and get trapped water toward the sump while on the ground, so that it would be less likely to happen in flight.

In the 172S, the only reasonable way to do that was add more low point drains.

 

[Riggerrob]

The ideal fuel tank would be tall and narrow - like those installed in the landing gear legs of the one-off Drako. Mike Patey made those unconventional fuel tanks to avoid un-porting the feed line during steep STOL take-offs.
Oh! And the landing gear legs are close enough to the center-of-gravity to minimize balance problems when fuel weigh changes.

How you incorporate a tall, narrow fuel tank in any other airplane is a mystery ... no CHALLENGE ... to the next generation of designers.
Perhaps install a header tank in the engine pylon of a Lake Amphibian??????

 

[Dan Thomas]

Perhaps install a header tank in the engine pylon of a Lake Amphibian??????

Ha. Might get 5 or 10 gallons in there. It's a tight spot. Full of engine control cables too. The main tank is directly below it. And we'd need more pumps, one to lift the fuel from the main to the header, another to lift it from the bottom of the header to the engine, and backups for both of them.

 

[Dan Thomas]

Another place for fuel troubles: The Cessna 177 has a weird venting system. The vent lines come out of the outboard sides of each tank, run around the tank to the rear and then across the inside top of the fuselage into the other wing and all the way to its tip, where the outlet is hidden between the aileron end and outboard rib. This is to the stop the typical fuel dripping from the vent when the tanks are full and the airplane is parked one-wing-low. The fuel would have to climb uphill from that low tank all the way to the upper wing's tip, and it ain't gonna do that.

Now, there are tees with plugs in them in the wing roots to drain water and crud from those lines. Guess how many get pulled out at annual? Statistically insignificant, that's how many. Suppose water accumulates in there and freezes? Now we have venting issues.

Airframe manufacturers have airframe-specific inspection checklists for good reasons. FAR43 Appendix D is way too general to tip off the mechanic about some of this stuff.

And a 1996 Citabria we bought in about 2003? Had no tank sump quick-drains. Just plugs. From the factory. Never out in seven years. Now that's something that should never happen. It's insane. Cessna built some like that too, a long time ago. I recall an old SB addressing it.

 

[Bigshu]

I ran into a water issue where I gotrefuled a C-172 before I took off, I drained a fuel sample before & after the refueling they were good. I took off from Ogden Utah headed to Black Foot Idaho. I flew north to Brigham City, then turned east south of Logan while over the mountains between Logan Utah & Bear Lake the engine started running rough. I landed at Soda Springs airport talked to the mechanic at the FBO their he said to wait about 1/2 hour. So I used their restroom & drank some coffee he brought out a bucket to the plane & we drained 1.5 gallons waterout. He said he'd call the FBO I got the water from. I also never used that FBO again

I had a similar experience many years ago with my Dad flying home from Iowa in a Grumman AA1. We had flown up from KC on full tanks. Only used about half a tank getting there, so we landed not long after switching tanks. A couple of days later, Dad sumped the tanks, had the FBO top off the low one, checked for water after, and launched for home. About half way home, switched tanks, engine sputters and dies. This is in early Feb, so all the fields below us were snowy and frozen. The old man switched back to the other tank, and cranked for a while before it caught. Quiet flight home! Checked the right tank after landing, found about 4 gallons water. Called the FBO to let them know. Turns out, the FBO says frost heave had cracked a pipe, and their fuel tank was about half full of water. I guess from the surrounding soil. I was around 12 at the time, so didn't get too concerned, but my Dad was pretty white knuckled until the engine restarted.

 

[[email protected]]

Glad you had little altitude under you! AA1, A, B or C is no glider.

 

[challenger_II]

They glide better than the Space Shuttle!

Glad you had little altitude under you! AA1, A, B or C is no glider.

 

[Richard Roller]

Another place for fuel troubles: The Cessna 177 has a weird venting system. The vent lines come out of the outboard sides of each tank, run around the tank to the rear and then across the inside top of the fuselage into the other wing and all the way to its tip, where the outlet is hidden between the aileron end and outboard rib. This is to the stop the typical fuel dripping from the vent when the tanks are full and the airplane is parked one-wing-low. The fuel would have to climb uphill from that low tank all the way to the upper wing's tip, and it ain't gonna do that.

Now, there are tees with plugs in them in the wing roots to drain water and crud from those lines. Guess how many get pulled out at annual? Statistically insignificant, that's how many. Suppose water accumulates in there and freezes? Now we have venting issues.

Airframe manufacturers have airframe-specific inspection checklists for good reasons. FAR43 Appendix D is way too general to tip off the mechanic about some of this stuff.

And a 1996 Citabria we bought in about 2003? Had no tank sump quick-drains. Just plugs. From the factory. Never out in seven years. Now that's something that should never happen. It's insane. Cessna built some like that too, a long time ago. I recall an old SB addressing it.

Cross venting, left tank to right tip, etc., Is common on commercial a/c. The MD-80 series and the DC-9'S were all vented that way. I believe 727's also.

 

[Turd Ferguson]

Another place for fuel troubles: The Cessna 177 has a weird venting system. The vent lines come out of the outboard sides of each tank, run around the tank to the rear and then across the inside top of the fuselage into the other wing and all the way to its tip, where the outlet is hidden between the aileron end and outboard rib. This is to the stop the typical fuel dripping from the vent when the tanks are full and the airplane is parked one-wing-low. The fuel would have to climb uphill from that low tank all the way to the upper wing's tip, and it ain't gonna do that.

Perhaps that was good in theory but at least by 1970, the Cardinal flavor I had, there was a note in the Owners manual about it:

NOTE
When parking the aircraft with full fuel bays on an inclined parking ramp, a significant amount of fuel could seep through the bleed hole in the fuel line check valve of the depressed wing during an overnight tie-down. To minimize fuel loss during this condition, the fuel bay capacity in the low wing should be limited to 22 gallons, (indicated by a series of holes inside the filler neck), in addition, the fuel selector valve should be placed in the "RIGHT" position to prevent cross-flow transfer from the fuel bay in the high wing. The fuel levels should be checked visually and replenished as required before starting
an extended cross-country flight.

That seemed to work okay unless you had a flat main tire with full tanks, which then fuel would profusely dribble out of the low wing vent.

The other hazard I encountered was the vent line at the trailing edge was held in position by a simple tube clamp anchored to the plastic wing tip with a PK screw and Tinnerman nut. That came loose once and the fuel line was free to spring into the cove in the end of the aileron, somewhat limiting aileron travel. My preflight was always check the security of the vent line at the trailing edge and poke a custom make wire prod several inches into the tube to ascertain no mud daubers.

 

[Toobuilder]

I can remember "spinning" a C-177 at EOR to check for traffic, and with a full fuel load it would sling fuel from both vents like a lawn sprinkler.