quote:

Originally posted by sns3guppy:
I was told to "inspect them, but don't find anything." Clearly two different concepts.

Our IA believed it was his job, his responsibility, to find things wrong with an aircraft he was inspecting...in fact, I think he derived some perverse pleasure in both finding a squawk issue and informing the owner about it. He didn't get creative or "invent" any issues, but he didn't sweep them under the rug either. In some cases he grounded the a/c until the issue(s) were repaired, in other cases he signed off and returned the a/c to the owner for flight but part(s) were ordered with the understanding that repairs would be effected and the a/c was placarded if appropriate.

Not a single a/c that he inspected sailed through an inspection without some sort of squawk or gripe and repair...and he was proud of this fact.

You can't be a competent IA without growing some thick skin and bruising a few egos.

During an annual inspection, any discrepancies become the owner/operators responsibility. It's just the inspector's job to find them. The owner can always decide not to have the inspector correct them, or can take them elsewhere.

Inspectors who make a habit of rubber stamping items quickly earn a reputation that repels those who are serious about safety, and attracts those who are concerned only with the cost.

Owners who make a habit of not getting squawks fixed quickly earn a reputation among inspectors and mechanics: avoid that owner.

quote:

Nor did the report explain why the missiles onboard the jet did not explode, or whether it was a concern about an explosion or exposure to a toxic chemical in the ejection system that prompted authorities to repeatedly push back people who had gathered near the crash scene

The missiles didn’t go boom, because they had not been armed and the small fire was extinguished preventing the warhead from detonating.

The plane didn’t go boom, because the pilot had the forethought to burn off most of the jet fuel.

And it’s just wise to keep people away from a wrecked (insert item here) to keep people from hurting themselves or making things worse...

Why does that have to be spelled out in a report as to why the plane quit flying?

Critical thinking is lost on some people.

quote:

Originally posted by MikeinNC:

quote:

Nor did the report explain why the missiles onboard the jet did not explode

The missiles didn’t go boom, because they had not been armed and the small fire was extinguished preventing the warhead from detonating.

And in all likelihood, since they were doing 'practice intercepts', they didn't have actual 'missiles', but CATMs (Captive-Air Training Missile), which have no warhead, no rocket motor, only electrical systems to help aircrew train to utilize them and ordnance personnel to load / unload them.

A previous post notes:

quote:

The missiles were eventually taken to Ben Clark Training Center, where they were detonated.

Well considering how wonderful the rest of the reporting is, I'll take that with a grain of salt.

quote:

The crash of the P-51 "galloping ghost" at Reno a few years ago, which lost control and crashed in the grand stands, killing a number and injuring many, was the result of one tiny little fiber lock nut on the elevator trim tab...a nut that shouldn't have been re-used, but was. It vibrated loose, caused flutter, caused the controls to fully deflect so hard that it knocked the pilot unconscious in the ensuing loop...that terminated in a power dive into the grand stands.

My mentor, Jimmy Leeward, RIP. See my avatar.

I'm an AP/IA, but work only on my own planes. I also sign them off, but •always• have another knowledgeable AP review my work/inspection/logs - just in case.

This message has been edited. Last edited by: aileron,

Here's a sort of similar story, with a post-maintenance problem.

A few years ago, I flew a client and his wife, in his Bonanza, to Stella Maris, Long Island, Bahamas.

We were supposed to depart Orlando at 7:00 am, but they did not show until almost noon. This was supposed to be a drop and run for me, turning around and returning to the U.S., but by the time we got to Stella Maris and I competed the Bahamian arrival paperwork it looked like my arrival back at Fort Pierce FL, to clear customs and immigration, would be pushing sunset. I was not thrilled about the possibility of something going wrong, and floating around on a life raft after dark, so it was decided that I would overnight there, and return home the following morning.

Good plan!

The next morning, after breakfast, I departed, climbed to my cleared altitude of 6,000', and settled in for the 425 mile trip. Approaching New Providence Island, there were some cumulus build-ups at my altitude. Not really a problem, but I'm too old to enjoy bumping around when there's a smooth ride available on top, so I called Miami Center and requested a climb to the next higher west bound altitude, 8,000'.

The request was approved, I increased power for the climb, and after leveling out at the new altitude, I reduced to cruise power setting, and fine-tuned the fuel / air mixture for the new altitude. At lease, I tried to do that. The mixture control lever just flopped around as if it wasn't attached to anything, mainly because at this point it really was not attached to the fuel controller any more. By this time I was about equidistant between New Providence and the U.S. coastline, so I elected to continue after informing Miami Center of my problem.

I'm not an aircraft mechanic, and I didn't really know what the mixture control would do in this situation -- stay in the last set position held by friction? Flop around randomly? No idea. If the mixture decided to migrate all the way to the lean position, the engine would stop (fuel starvation) and the airplane would be taking a salt water bath. I pulled the life raft package up to the unoccupied co-pilot seat, just in case.

The engine kept running, I made it back, landed, cleared U.S. customs and immigration, then got a maintenance guy to check the problem. The business end of the mixture control cable in the engine compartment was not connected to anything. Nothing broken, but the mechanic retrieved a machine screw, two flat washers, and a castle nut that had fallen off. All the necessary parts except the cotter pin that should have secured the castle nut in place. Did I mention that the airplane had been in the shop for maintenance the day before our departure?

The mechanic started to re-assemble the cable end, pushing the machine screw in toward the inboard side of the fitting. I asked whether it could be assembled from the opposite direction, with the nut facing outward. He asked why I wanted it that way, I replied that the nut would then be visible during pre-flight inspection. He did assemble it per my request. When I got home, I had our mechanic reverse the fitting on my own Bonanza, so that I would be able to see it for visual inspection. Lesson learned.

From that point on, whenever I had a trainee with his / her own Bonanza, I suggested that they reverse the assembly from the factory setting. The default for machine screw insertion is top to bottom, fore to aft, and outboard to inboard, but this can be changed if there is a good reason.

quote:

Originally posted by aileron:
My mentor, Jimmy Leeward, RIP. See my avatar.

Sadly, Leeward had no chance; a the speed he was racing, the controls went hardover, and there was no possibility of him effecting a recovery, even had he regained consciousness. The sliding scale, standard for a fiberlock, is can it be threaded on with finger pressure alone? If not, good. If it can, don't re-use. In an application that critical, probably best not to re-use, but tens of millions of fiberlocks are reused.

I went through a shelf of them at a repair station years ago, and rejected every single one.

As an IA, you know that...but a lot of mechanics don't seem to know that, which should be pause for real concern. I've seen mechanics do idiotic things like put RTV silicon on the threads to get the nut to hold, or put a lock washer under it, neither of which are acceptable for a fiberlock. Even locktite (still not acceptable). Shadetree mechanics at best.

A few years ago in Mosul, Iraq, I wandered into a hangar where a mechanic was doing a governor change on a Cessna 337/O-2 Skymaster. I asked why. He said the governor had jammed, and the pilot couldn't move the propeller control. I pointed out that governors don't do that; they fail typically to an unregulated position, like a fixed pitch prop. The mechanic said he had no idea, but was changing the governor to be sure.

While we talked, I examined the governor. Sure enough, the failure was obvious: someone had wrapped safety wire around the control arm, locking it in place. The result was that the governor was wired into the high-RPM position, with no ability to feather the propeller. Had that airplane experienced a failure of that engine, the airplane would have gone down in Indian country...absolutely no chance of flying that skymaster back to the airport with one windmilling. And the pilot knew he couldn't move the prop control before he took off. Stupidity hurts.

What about the guy that safety wired it in place, inadvertently? What about the mechanic who decided to change it out, having no idea why it failed, or even that it was safety wired in the wrong position? Both those guys were actively working on aircraft, with some apparent serious gaps in their understanding of function in the equipment they maintained.

quote:

Originally posted by sns3guppy:

What about the guy that safety wired it in place, inadvertently? What about the mechanic who decided to change it out, having no idea why it failed, or even that it was safety wired in the wrong position? Both those guys were actively working on aircraft, with some apparent serious gaps in their understanding of function in the equipment they maintained.

Very tragic mistakes, but when humans are involved, there is always a possibility. Lord knows pilots have made their fair share, to keep things in perspective.

In that particular incident, in the O-2, the pilot error was taking off with the prop control hardwired to the high RPM position.

Pilot error is the case in the vast majority of mishaps, and even in many mishaps when maintenance errors exist, ultimately it's still the pilot who causes the actual mishap.

The Swissair 111 MD11 off the coast of Nova Scotia is a good example. The onboard fire was a very real threat, and the fault of wiring in an onboard entertainment system in the MD11. The aircraft was in a position to make a landing, and should have done so. The crew elected to out to sea and take time to dump fuel down to landing weight; that time cost everyone their lives. That, and following the smoke checklist (because shutting off cabin air using the smoke/elec switch caused the fire to propagate toward the cockpit). The pilots didn't cause the fire, but their decision making proved fatal.

UPS 6 was a similar end, a 747-400 that should have landed in Doha, instead of returning to Dubai. The crew did not cause the fire, but in each case, a different decision might have led to a very different outcome.

At 250', the F16 pilot didn't have a lot of options, other than to leave the aircraft.

quote:

or exposure to a toxic chemical in the ejection system that prompted authorities to repeatedly push back people who had gathered near the crash scene.

I know the F-16 utilizes an EPU which has hydrazine but, what's in the ejection seat that would be toxic?

quote:

Originally posted by aileron:

quote:

The crash of the P-51 "galloping ghost" at Reno a few years ago, which lost control and crashed in the grand stands, killing a number and injuring many, was the result of one tiny little fiber lock nut on the elevator trim tab...a nut that shouldn't have been re-used, but was. It vibrated loose, caused flutter, caused the controls to fully deflect so hard that it knocked the pilot unconscious in the ensuing loop...that terminated in a power dive into the grand stands.

My mentor, Jimmy Leeward, RIP. See my avatar.

I'm an AP/IA, but work only on my own planes. I also sign them off, but •always• have another knowledgeable AP review my work/inspection/logs - just in case.

I know his son Chad. My customer/friend is very good friends with him and they go flying together often. He's a very nice guy. It was a very sad/tragic accident.

An instructor in college told us once, and this always stuck with me... "If you make a mistake designing or repairing a car, it pulls to the side of the road. If you make a mistake designing or repairing an aircraft it will dig a big smoking hole in the ground."

quote:

Originally posted by V-Tail:
From that point on, whenever I had a trainee with his / her own Bonanza, I suggested that they reverse the assembly from the factory setting. The default for machine screw insertion is top to bottom, fore to aft, and outboard to inboard, but this can be changed if there is a good reason.

Good idea. Some folks take "In, Aft, and Down" as religion, but this seems like an excellent place for an exception.

quote:

Originally posted by Rightwire:
An instructor in college told us once, and this always stuck with me... "If you make a mistake designing or repairing a car, it pulls to the side of the road. If you make a mistake designing or repairing an aircraft it will dig a big smoking hole in the ground."

Early in my flying career I was driving home, late at night, tired, working to stay awake. The engine in that tired old '74 Toyota pickup had a little hiccup and I just about had a heart attack. Then I realized I was in a pickup, not an airplane, had lots of safe places to pull over, and wouldn't even have to walk that far to get home. Laughed at myself, but I was wide awake the rest of the way home.

Funny how flying low, or flying over open water, or flying at night, one hears all kinds of things, whether they're there, or not. The fewer the engines, the louder the sounds.

With regard to this incident, a couple of things to clarify.

The "technician(s)" installing the ISA (Integrated Servo Actuators) do not have any dealing with the check valves. There are 5 ISA's used in the F-16, and each responsible for left and right flaperon, left and right horizontal stab, and the rudder. The rudder ISA is unique to the rudder, and the other four are interchangeable.

It is a complete assembly.

Think of it as a transmission on a car, the mechanic may replace the transmission as a unit, having it rebuilt at a higher level depot facility, and being torn down, inspected, built up, tested and then sent out and replaced in the field, and then ops checked.

Many components can be installed, and ops checked and pass checks, and later fail in flight due to the nature of the limits of operational checks.

(you cannot tow an aircraft at Mach. You cannot jack an aircraft to 40-60 thousand feet, and you cannot push it around to 3-9 Gs, while it is sitting its happy ass on the ground...)

The time to have caught this particular problem was at the depot level repair facility where the rebuild was done and testing to certify the assembly.

In the end, training, effective system design, and many people doing their job correctly allowed the pilot to do everything correctly and live. The investigation will help create procedures to help prevent a similar incident in the future.

This is the nature of the military (and other) aviation.

Imperfect people, creating imperfect machines, stuff is gonna happen.

If that is too hard to deal with, find a safe place, close your eyes and hum.

Maybe bad things will not happen.

Maybe...

(I spent the best years of my life making sure the best things were done to facilitate safe and able aircraft. I was "ate up" and "anal as could be" about it, and for good reason. I told my troops on many occasions, that "Our job was to make sure the aircrew got to step over the threshold of their house, and kiss their dog and pet their wife or vise versa. We don't care which way they do that, but we will do everything in our power to make sure they get to choose...")

That came from being on both sides of the game, as an aircrew member and as Crew Chief as well as "picking up the pieces"...)

I never regretted any and all effort. I only regret that I could not do it my entire life.

(and other things, stay with you for life)

quote:

Originally posted by sns3guppy:
Funny how flying low, or flying over open water, or flying at night, one hears all kinds of things, whether they're there, or not. The fewer the engines, the louder the sounds.

You speak the Truth.

quote:

Originally posted by sns3guppy:

Funny how flying low, or flying over open water, or flying at night, one hears all kinds of things, whether they're there, or not. The fewer the engines, the louder the sounds.

When flying single engine over water, the engine usually goes into "auto-rough" as soon as you're beyond gliding distance to land.