Trust, but verify

[Herk Fixer]

Hey all,

This is a message I posted last month to the AOPA forum.  I think it's a good discussion topic, so I thought I'd share with you as well:

I recently attended an ASF seminar on Emergency Procedures. The speaker put on an excellent program; and the attendence was good. One of the items he touched upon dealt with maintenance issues, specifically mis-rigging of flight controls. The example he used was the Spectrum experimental jet crash from July, where the sidesticks were rigged to produce opposite roll control from what was input. It reminded me of a crash from 1992 in Hot Springs, Arkansas which killed three people....the mechanic accidentally left a half-turn from the aileron cable drums at the yokes, such that the ailerons moved opposite of yoke input. The inspector didn't catch it, and he died along with the two pilots when the airplane rolled and crashed on takeoff.

Before I get hate mail from AMT's: for the record, I've been in maintenance (since 1989..A&P in 1995) far longer than I've been a pilot (since March). It's not my goal to insult good mechanics; rather I hope to save a life by reminding pilots to look and verify proper operation anytime work has been done on a critical system.

Two incidents I have knowledge or involvement with both have 727's as the player. In the first, engine work had been accomplished that required a performance check on all three. With the work completed, the crew came out for a reposition flight. It wasn't until the throttles were advanced for takeoff was it discovered that the stops on the fuel controllers for #2 & #3 engines were safety wired in the part-power position!

In the second, an airline I used to part-time contract with gave me a call one morning to take a look at an airplane that was inbound to KOKC. Apparently they were having "pitot-static problems" of some sort. When the airplane taxied in, I immediately zeroed in on the problem. All of the right side static ports were covered...with speed tape (a no-no)! Overnight in Detroit, maintenance had performed a transponder check. The logbook had been signed off, and the flight engineer didn't see the tape (matched the color of the airplane and wasn't flagged....that's why speed [aluminum] tape is a no-no for static ports...). I don't understand why the crew continued to fly the airplane x-country when it was apparent only half of the pitot-static instruments worked.... With this, and another discovery of poor maintenance, I didn't contract for them any longer!

The bottom line is this...yes, you have to be able to trust your mechanic for work performed on your airplane, but if that work involves a critical component (like flight controls, or engines) take the time to verify the work was done properly!

[tundra_flier]

One of the items he touched upon dealt with maintenance issues, specifically mis-rigging of flight controls. The example he used was the Spectrum experimental jet crash from July, where the sidesticks were rigged to produce opposite roll control from what was input. It reminded me of a crash from 1992 in Hot Springs, Arkansas which killed three people....the mechanic accidentally left a half-turn from the aileron cable drums at the yokes, such that the ailerons moved opposite of yoke input. The inspector didn't catch it, and he died along with the two pilots when the airplane rolled and crashed on takeoff.

I keep hearing about this exact type of accident, and it keeps baffling me.  Even when I was flying Radio control planes we always checked control direction before take-off.  Heck, my 150 has that in the checklists 3 times berore takeoff.  Is it not possible to see the ailerons from the cockpit of some planes?

In the second, an airline I used to part-time contract with gave me a call one morning to take a look at an airplane that was inbound to KOKC. Apparently they were having "pitot-static problems" of some sort. When the airplane taxied in, I immediately zeroed in on the problem. All of the right side static ports were covered...with speed tape (a no-no)! Overnight in Detroit, maintenance had performed a transponder check. The logbook had been signed off, and the flight engineer didn't see the tape (matched the color of the airplane and wasn't flagged....that's why speed [aluminum] tape is a no-no for static ports...). I don't understand why the crew continued to fly the airplane x-country when it was apparent only half of the pitot-static instruments worked.... With this, and another discovery of poor maintenance, I didn't contract for them any longer!

You know I've always wondered, what type of preflight inspection is typically done on airliners?  I must say I've never seen an airline captain out walking around the plane before a flight. 

Phil

[cj5_pilot]

Tundra you don't have to worry so much...you're usually helping the mechanic on your plane 

Funny we should mention pre-flights.  The flying club I belonged to down in Kenai (Alaska Flying Network) had 4 planes at the time.  A pair of 152s, a 172 and a 210.  Chip the owner felt some of the guys were not taking their time in pre-flight.  He challenged all the members to a "pre-flight contest".  He took the plane to the maintanence hangar and delibertly made things wrong with it (13 IIRC).  He then gave each pilot 3 minutes to preflight.  The prizes were 5 hours of flight time, a electronic pocket E6B and 2 hours of flight time.  Since I'd recently gotten my license and was hogging as much time as I could, I decided to give it a whirl, hoping to win first or third place. 

Now each pilot was given 3 minutes WITHOUT a checklist.  Both those were issues for me as I'm something of a slave to the checklist and I generally took a minimum of 20 minutes to preflight.  I missed three of the things.  IIRC One was a missing cotter key and loose nut on a wheel, one was a missing inspection plate (under the horizontal stabilizer and I was pressed for time) and the one that was totally something I normally wouldn't check (and ain't on the checklist) was that he's switched the covers on the wing tip lights, so they were the opposite color!

I had felt rushed through the entire deal and would NOT have flown the plane had I done an actual preflight that fast (not to mention the short dozen other items I DID find--which did include no POH).  Turns out I took second place and one the flight computer.  Several guys only noticed 1 or 2 things wrong!

Following up on Herk Fixer:  Trust but Verify.  Especially if you fly in a flying club with communal aircraft.  Just because a plane just came in from a safe flight with another pilot don't mean something's not wrong and you don't need to do your walk around.

[Baradium]

One of the items he touched upon dealt with maintenance issues, specifically mis-rigging of flight controls. The example he used was the Spectrum experimental jet crash from July, where the sidesticks were rigged to produce opposite roll control from what was input. It reminded me of a crash from 1992 in Hot Springs, Arkansas which killed three people....the mechanic accidentally left a half-turn from the aileron cable drums at the yokes, such that the ailerons moved opposite of yoke input. The inspector didn't catch it, and he died along with the two pilots when the airplane rolled and crashed on takeoff.

I keep hearing about this exact type of accident, and it keeps baffling me.  Even when I was flying Radio control planes we always checked control direction before take-off.  Heck, my 150 has that in the checklists 3 times berore takeoff.  Is it not possible to see the ailerons from the cockpit of some planes?

Some aircraft it can be difficult to see all the flight controls from the cockpit.  Dont' forget the elevators either.    In some airliners, the wings are so far behind the cockpit that you might not be able to see the ailerons (think 727).

You know I've always wondered, what type of preflight inspection is typically done on airliners?  I must say I've never seen an airline captain out walking around the plane before a flight. 

Phil

The most thorough preflight is done for the first flight of the day, but there is a preflight done before each flight as well.  You just probobly don't notice it, also the captain might not be the one to do it (could be the F/O).

[switchtech]

The most thorough preflight is done for the first flight of the day, but there is a preflight done before each flight as well.  You just probobly don't notice it, also the captain might not be the one to do it (could be the F/O).

I imagine this happens more often on bad weather days... 

My flight instructor always had me re-preflight after even brief stops on cross country flights if the aircraft was ever out of sight (like when getting that $100 burger).  You never know when an animal may have decided to get warm in the engine (not that often in South Texas, I'm sure) or when a mischievous kid messed with your plane (let the air out of the tires, put gum over the pitot, etc).

jbs

[spacer]

A kid like that where I worked would likely get a bird-bomb in the keester.

Our flight instructors were assigned to test-fly our birds after any work requiring it.
I kept my logbook in my pickup, and the pilots were quite happy to have me along
(especially when it was after an engine-swap).

[tundra_flier]

While on the subject of preflights - One of things I've never seen any other pilot do is dip the tanks before a second leg.  Especially on a short burger run.  This really hit home to me after I was on a Navajo that had to turn back when a fuel cap started leaking.  In the Navajo it was pretty visible streaming back from the cap, in a cessna you'd never see it.  Not to mention the number of people who think Avgas will make their 4 wheeler or snowmachine faster.

Phil

[Gulfstream Driver]

Not to mention the number of people who think Avgas will make their 4 wheeler or snowmachine faster.

No road tax on Avgas.   

[tundra_flier]

No road tax on Avgas.   

It's still about a $1 a gallon above auto though.  And I have heard of people getting stranded in a village because someone siphoned out all their fuel, and no one would sell them any.

Phil

[Gulfstream Driver]

Wow, that's pretty harsh. 

[tundra_flier]

Yeah, thank god my little O-200 likes its 87UL.  Her new home came with a 250gal fuel tank, so next summer I can get unleaded without road tax too. 

Phil

[FB41]

... or when a mischievous kid messed with your plane (let the air out of the tires, put gum over the pitot, etc).

jbs

Or some dirtbag steal your $75 (EACH!) gas caps off your Aztec. That happened to me once and I didn't catch it until I was airborne and noticed fuel straming from under the gas cap cover!
That broke me of my habit of doing a thorough pre-flight for the first flight and then trusting myself- and others- afterward. Now the plane gets a walk-around if it ever gets out of my sight, regardless of how long!

[cj5_pilot]

Only the gascaps?     I lost a whole plane once.   I had refueled at Hudson's in Talkeetna and while I was in paying some other pilots pushed it out of the way to fuel up and they pushed it around the corner of the building!  I came back and just about had a cardiac arrest!  The other guys immediately realized why I was about to freak and pointed me in the right direction.  What a heart stopper!  I know it sounds funny, but I get nervous when I'm out of sight of the airplane.  I ended up tying down at transient and running in to town for a burger.  Then I came back did a full preflight and headed back to Palmer then Kenai.

[spacer]

When I drove trucks, I got nervous when I was away from my tractor. Not only was it my rolling home, but it was my ticket back to my hometown. I feel pretty much the same way with an airplane, but without the 'rolling home' aspect.
My Freightliner was burglarized once, and about $1200 worth of stuff was stolen (not to mention the window repair). I felt so... violated.

[chuckar101]

Its quite amazing what people will steal out there and then our reactions.  I have had several gas caps stole off my truck.  So I went out and bought a locking cap and always check if its there before i leave.  Anybody else pick up any little quirks after something has been stolen from them.