Cracked spars on Seneca's

[CDVdriver]

Pulled this off another forum.
12 out of their 18 Seneca's have spar cracks.
Curious as to what Piper and the FAA are going to do.
AD's?

www.oxfordaviation.net/forum/topic.asp?TOPIC_ID=1467

 

[avbug]

Same thing happened at a firm where I flew some time ago. Several pilots at a particular station who were flying Seneca II and III airplanes called me to tell me about an aircraft that made a popping sound each time they applied flaps on the base leg. They'd reported it to maintenance, each time the response was that it couldn't be duplicated, and nothing appeared wrong with the rigging or pulleys.

I happened to stop by that facility and ran into the Director of Maintenance, a good friend. I enquired about that airplane, and he invited me into his office. Yes, he knew about it, he said. A pilot had brought it in a short time ago, and complained about the popping noise. As he'd been unable to hear it in the hangar, he asked the pilot to fly him around the pattern so he could hear it himself.

"We were taxiing out, and I felt the floor moving under my feet. I immediately cancelled the flight and told the pilot to taxi back to the hangar." He had been very concerned.

Upon opening up the airframe, the spar was found cracked in three places. The popping sound had been the spar repositioning against itself under a load. The aircraft was immediately grounded, and I don't recall hearing about it again.

With the number of incidences of this same thing you describe, most certainly an emergency AD should be issued. Yikes.

 

[CDVdriver]

Was that RamAir by any chance?

 

[avbug]

No, it wasn't. That particular company, like many of my former employers, is no longer with us...another testament to the stable nature of the industry.

Alrighty then...I just reviewed the web board reference you cited. It doesn't say anything about cracked spars. It appears to indicate that cracks were found in the gear trunions, though this isn't definitive due to the ambiguous nature of the way the owner reported the problem.

I have seen this also in the Seneca II, in an airplane that reported gear problems. I saw several of the attach bolts where the trunion mates with the spar box that were badly deformed and sheared and the situation had become so bad that the gear could be moved around by hand while down and locked with the aircraft on jacks. Obviously it was grounded and repaired. I don't recall actual cracking of the trunion or other fittings, but elongation of holes and fretting damage. Without considerable more information, attempting to relate the two situations would be pointless. In the case of the trunion which I saw, incorrectly sized bolts had been used in several places in the installation, leading to the failure.

From the link you posted, I don't see any sign so far that each airplane was experiencing spar cracking. The cracked spar I cited previosly is the only one on a Seneca I've seen. If it's being found on numerous other aircraft, however, then it most certainly does need to be addressed. From the tone of the post, the school immediately inspected all their aircraft, grounded any that were questionable, and immediately got the British government and Piper involved in seeking a soloution and approvals. Seems that everyone is on track, aware, and working toward a soloution.

 

[CDVdriver]

Could only find one spar AD for the Seneca, it's from 1974.
And it deals with the "lightening holes" in the spar unlike what's going on now in the UK.

 

[avbug]

I edited in some more comments, see my previous post.

 

[CDVdriver]

Ah, you were talking about a broken spar, but that was clear already.
Seems more then just coincidence that 12 out of 18 (probably high time) planes have similar cracks developing.
Even though they are called "very small cracks".
It would surprise me if this would not turn into an AD.
Not trying to raise a panic here, but still a little on alert here after that Cessna AD on the wrongly assembled flight controls.
We'll see where this leads.

 

[EagleRJ]

That particular company, like many of my former employers, is no longer with us...another testament to the stable nature of the industry.

...or it could be testament to your overall degree of luck in this industry!

Sorry, couldn't resist!

 

[avbug]

Ah...a lot of furloughed pilots and folks out of work due to bankrupt companies, airlines, corporate flight departments, yada, yada...all seem to share the same luck. They used to not be able to resist until it wasn't so funny to them any more, too...

 

[Fuzzy_is_Hungry]

... It appears to indicate that cracks were found in the gear trunions ...

This just happened to a friend of mine who flies a Seneca II. All but one of the bolts had sheared off and the mechanic almost had the gear collapse driving it into the hangar.