Van Nuys Twin Nose Gear Failure Happening Now

[KennyFlys]

But Kenny- the gutless Cutlass had a serious AD on those hydro packs! I helped replace them in the 172RG's we had as trainers at our school. Some of them even had to sit for a year or more, waiting for parts to come available.

If I remember correctly, the AD had to do with cracks in the housing, but related to the metal /casting... not number the of cycles.

But, what were the cause of the cracks? Was it weak construction alone or was it fatigue from the extraordinary number of cycles?

 

[Everskyward]

Of course equipment will fail if not properly inspected, but there's equipment that's easy to inspect and doesn't fail as often and equipment that's difficult to inspect and fails rather often. Sadly, retract Cessna twins generally fall into the latter category (this was a very common failure mode for Cessna tip tank twins if I understand correctly).

I agree with this. I had the nosegear on a Cessna 320 fail 10 hours out of annual with a reputable mechanic. The FAA people who came to inspect basically said, "This happens a lot." They didn't ding the mechanic for poor inspection processes. If anything is poor it's the design. There are a lot more moving parts than on other gear systems. Obviously they need to be in rig but even if they are, there are other things that can fail. The part that failed in this case was the push-pull tube which pushes the nosegear forward. It apparently bent and then broke. This part is in a hidden place between the floor and the skin if I remember correctly. Since the nosegear extends forward, it won't freefall against the airflow and lock, nor will it crank down since at that point you are only cranking the box.

 

[RotorAndWing]

I agree with this. I had the nosegear on a Cessna 320 fail 10 hours out of annual with a reputable mechanic. The FAA people who came to inspect basically said, "This happens a lot." They didn't ding the mechanic for poor inspection processes. If anything is poor it's the design. There are a lot more moving parts than on other gear systems. Obviously they need to be in rig but even if they are, there are other things that can fail. The part that failed in this case was the push-pull tube which pushes the nosegear forward. It apparently bent and then broke. This part is in a hidden place between the floor and the skin if I remember correctly. Since the nosegear extends forward, it won't freefall against the airflow and lock, nor will it crank down since at that point you are only cranking the box.

If anything is poor it's the design. There are a lot more moving parts than on other gear systems.

Really? It's actually about the same as a Beech system parts wise. All push tubes (Beech does use cables and chains).

The part that failed in this case was the push-pull tube which pushes the nosegear forward. It apparently bent and then broke. This part is in a hidden place between the floor and the skin if I remember correctly.

Yep, and what usually happens is because it's in such a tight spot, the mechanic doesn't bother to inspect it, hence the failure.But it can be inspected, just follow the MM, it has a very detailed inspection step by step.

And the reason it fails is because your LG is out of rig, because it was never inspected properly. These tubes just don't bend and break for no reason. It's all in the landing gear asymmetry.

Tony Saxton of TAS is a very knowledgeable mechanic on Twin Cessna's and even produced a detailed video on inspecting the gear system. Once again maintenance is key to this and any other airplane's gear system. Most mechanics do not want to spend upwards of a day doing the inspection as it is outlined.

 

[RotorAndWing]

I agree with this. I had the nosegear on a Cessna 320 fail 10 hours out of annual with a reputable mechanic. The FAA people who came to inspect basically said, "This happens a lot." They didn't ding the mechanic for poor inspection processes.

That's because, in the case of most Airworthiness Inspectors they too don't have a clue to the inspection process. If they would have they would have realized the gear was out of rig, and the nose push pull tube was never properly inspected causing the failure.

There is no way 10 hours out of a real inspection that tube would have failed.

 

[Everskyward]

Once again maintenance is key to this and any other airplane's gear system. Most mechanics do not want to spend upwards of a day doing the inspection as it is outlined.

So are you saying that Beech mechanics are more diligent than Cessna mechanics? If it takes that much more effort to keep Cessna gear in rig than Beech gear then wouldn't you call that a flaw in the design too?

 

[RotorAndWing]

So are you saying that Beech mechanics are more diligent than Cessna mechanics? If it takes that much more effort to keep Cessna gear in rig than Beech gear then wouldn't you call that a flaw in the design too?

It's not a "flaw in the design" because a component has a detailed inspection procedure. Like any other complex aircraft, it requires a higher degree of maintenance. I have actually watched mechanics jack up a 400 series Cessna, run the gear up and down a few times and drop it back on the floor and sign it off.

I owned a 310Q for 10 years. When I sold it I taught the mechanic that would be maintaining it for the new owner how to do the gear inspection. We spent about 8 hours going through it. He was amazed, because in the shops he worked previously they never even looked at that part of the MM. I also gave him my tools for the gear inspection process (once again, it requires specialized tools to do it properly).

That 310 has about 4,000 hours on it and has never had a gear problem thanks to the proper maintenance that has been applied.

 

[Everskyward]

It's not a "flaw in the design" because a component has a detailed inspection procedure. Like any other complex aircraft, it requires a higher degree of maintenance

But if it requires a much more detailed and time consuming procedure than other aircraft of the same type I would call it a flaw, or at least a disadvantage, if was considering buying one.

I would probably feel the same way as you if this has not happened to me. I have about 2,000 hours in that particular airplane and if you eliminate the first 40 then I would have told you the gear was perfect... well except for the one time I found scraping around the nosegear doors.

 

[flyingcheesehead]

IMO, it's merely for safety. The Ma T/o and Landing weights are the same. But from my buddy's past experience, the tip tanks do not come near the ground, unless he loses control as the nose settles, and rolls it over.

Should this pilot decide to set up high, and shut off the engines and glide it in (as my buddy did), the props should be completely stopped prior to the nose touching. Especially if he feathers them!

My buddy didn't even have a prop strike! Which was a great thing as he had just overhauled the engines and stc'd 3 bladed props...

AAAAAAAAAGH. Stupid pilot tricks.

When the wheels leave the ground, your insurance company bought the airplane. IF you touch down safely, you bought it back. You're going to have a claim regardless (due to nose damage in this case), you're going to have an "incident" regardless, so why increase the risk by trying to be super-pilot and "save the engines?" I've also heard of accidents where mr. super-pilot tried to do this and totaled the airplane because they came up short of the runway.

The fact that this guy "succeeded" is irrelevant.

This reminds me of the other stupid pilot trick, which is to buzz the runway while some guy in a car on the runway reaches up to try to pull a stuck gear down. That's gonna seem pretty stupid when the plane accidentally drops a few feet and crushes the guy, or the car's driver goes a bit too fast and puts him in the prop. Again, the fact that some people have succeeded at this is irrelevant - It doesn't stop the NEXT guy from screwing up, it only encourages it to keep happening until somebody gets killed.

Rant off.

 

[Ted]

AAAAAAAAAGH. Stupid pilot tricks.

...

The fact that this guy "succeeded" is irrelevant.

I could see a similar argument for why flying in general is unsafe. "The fact that you've landed safely so far doesn't mean you will next time. Flying's unsafe. People die when planes crash!" What do we want to extend this to? Single pilot IFR? Flying a single engine aircraft? Flying any aircraft? Riding motorcycles? Driving? Getting out of bed in the morning?

I have found in general when people bash others for a technique/activity/whatever that they consider dangerous, it's because they themselves are uncomfortable doing it, and therefore assume that nobody else must be competent enough to safely handle the situation. Sorry, I just don't buy it. There's a lot of stuff that I can't do, but that doesn't mean that others can't do it. Furthermore, statistics don't mean that you or anyone else can or cannot do something, it only tells you what others have or have not succeeded doing in the past. So, with few exceptions, I'll try to let others choose for themselves and not bash them just because I can't do something that they may be able to. You can bash me for that all you want, that just supports my point.

 

[flyingcheesehead]

After a few thousand hours in various 300/400 Series Cessna's I never had an issue with the landing gear. And I attribute this to quality maintenance.

The MM has a detailed inspection and rigging of the gear system. As long as this is followed at every inspection interval the gear is extremely reliable.

You're both right.

This problem isn't limited to Cessnas by any means. I recently had the opportunity to spend a couple of days with Thomas P. Turner, Manager of Technical Services for the American Bonanza Society (ABS). At one point, Tom and I were discussing ABS's terrific program of monthly "service clinics" where owners of Beechcraft Bonanzas, Barons and Travel Airs can fly in and have their aircraft inspected by some of the foremost Beech mechanics in the country.

While Beech built outstanding aircraft, statistics indicate that they are involved in an alarming number of landing gear collapses.

And, of course...

When I first acquired my Cessna T310R 17 years ago, I initially had the maintenance done by the maintenance chief of the local FBO, a seasoned A&P/IA in his 40s by the name of Darwin. This particular FBO owned and operated two twin Cessnas for Part 135 charter -- a 310 and a 421 -- so I felt reasonably confident that Darwin knew what he was doing. When the aircraft came due for its first annual inspection on my watch, I asked Darwin to do it.

Since this was my third aircraft, I'd known enough to purchase the parts and service manuals and tried to learn all I could about the maintenance aspects of the airplane. While reading through the service manual, I was struck by the rather intricate procedure for rigging the electromechanical landing-gear retraction system, whose step-by-step description occupied at least 20 pages of the service manual. According to Cessna, this procedure was to be accomplished every year. So when I happened by the maintenance hangar and saw my airplane up on jacks undergoing a gear swing, I asked Darwin if he was going to perform the full-blown rigging procedure "by-the-book."

"Bad idea," Darwin told me with a been-there-done-that look on his face. "If we mess with any of those landing gear adjustments, we'll throw all the other adjustments off. The gear looked good and sounded normal during the gear swing. If it ain't broke, don't fix it."

When the annual came due a year later, Darwin had moved on to another company and so another A&P/IA named Tom did the annual that year. Tom was also an experienced twin Cessna mechanic. I asked Tom about doing the full gear rigging procedure as described in the service manual, and got pretty much the same reaction as I'd gotten the year before from Darwin: "Looks good, sounds good, ain't broke, don't fix it."

And so it went for my first five years as a Cessna 310 owner. Each year I had a different IA do the annual. Each year I asked about the service manual rigging procedure. And each year the IA told me that it was a bad idea to mess with the gear rigging.


Finally, my fifth annual inspection was done by yet another experienced twin Cessna mechanic named Phil. When I timidly asked Phil about doing the gear rigging procedure and mentioned that it had not been done in the five years I'd owned the aircraft, Phil looked horrified. "Of course we're going to rig the gear," said Phil. "It's very important on these airplanes, and it's really no big deal." Phil invited me to hang around and watch while he went through the gear rigging procedure step-by-step, by-the-book, and I did. The whole procedure took several hours, but wasn't particularly difficult. Not surprisingly, Phil found the gear significantly out-of-rig and had to make a bunch of adjustments to bring it within specifications.

Full article, and it's a good read for any piston airplane owner:

http://www.avweb.com/news/savvyaviator/187401-1.html

 

[RotorAndWing]

But if it requires a much more detailed and time consuming procedure than other aircraft of the same type I would call it a flaw, or at least a disadvantage, if was considering buying one.

Most aircraft owners never consider the maintenance aspect of aircraft ownership. This is why you see incidents like the one that started this thread. They often feel if it worked now, it will continue to work and they shop their maintenance based upon price, not quality of work.

 

[RotorAndWing]

You're both right.



And, of course...



Full article, and it's a good read for any piston airplane owner:

http://www.avweb.com/news/savvyaviator/187401-1.html

Good read, thanks!

 

[Everskyward]

Most aircraft owners never consider the maintenance aspect of aircraft ownership. This is why you see incidents like the one that started this thread. They often feel if it worked now, it will continue to work and they shop their maintenance based upon price, not quality of work.

The owner of this particular aircraft was fairly fussy about maintenance, as well as everything else, and the shop was a reputable shop. I don't know if the gear was rigged during the annual although you would have thought the FAA investigators would've looked into it and pointed it out if it had not been done. This happened 17 years ago so I don't remember too much about all the details.

 

[TangoWhiskey]

They took their sweet time getting out! Would you get out immediately, just in case a fire erupted? I sure would.

 

[flyingcheesehead]

They took their sweet time getting out! Would you get out immediately, just in case a fire erupted? I sure would.

I'd secure the airplane first, unless I actually saw flames. Mixtures, mags, master, fuel selectors off, etc...

 

[TangoWhiskey]

Of course... but the passenger isn't needed for that. The fire truck had time to pull up and the firemen get out before the passenger even started getting out. Maybe they were having trouble getting the door to unlatch.

 

[rubber314chicken]

AAAAAAAAAGH. Stupid pilot tricks.

When the wheels leave the ground, your insurance company bought the airplane. IF you touch down safely, you bought it back. You're going to have a claim regardless (due to nose damage in this case), you're going to have an "incident" regardless, so why increase the risk by trying to be super-pilot and "save the engines?" I've also heard of accidents where mr. super-pilot tried to do this and totaled the airplane because they came up short of the runway.

The fact that this guy "succeeded" is irrelevant.

This reminds me of the other stupid pilot trick, which is to buzz the runway while some guy in a car on the runway reaches up to try to pull a stuck gear down. That's gonna seem pretty stupid when the plane accidentally drops a few feet and crushes the guy, or the car's driver goes a bit too fast and puts him in the prop. Again, the fact that some people have succeeded at this is irrelevant - It doesn't stop the NEXT guy from screwing up, it only encourages it to keep happening until somebody gets killed.

Rant off.

I used to think that that would have been a good idea. Then I realized- you are transporting priceless (well, half million dollar) cargo (humans) in a plane that is generally worth a good bit less than that. Why put the more expensive thing at risk? Bend the airplane and save the lives of all pax. Seems like a good trade off to me.