William who is looking into buying a Coupe asked about corrosion and accidents:
>>>>>>>>>>>>>>>>>>>> There are corrosion related fatalities in the NTSB database: <http://www.ercoupe.info/?n=Main.Hartmutscsection> http://www.ercoupe.info/?n=Main.Hartmutscsection <http://www.ntsb.gov/NTSB/brief.asp?ev_id=20040315X00324&key=1> http://www.ntsb.gov/NTSB/brief.asp?ev_id=20040315X00324&key=1 As evidenced by the NTSB case, even very careful adherence to the AD's with the most prudent due diligence is sometimes not enough. <<<<<<<<<<<<<<<<<<<< William, Yep, that one gave us heartburn till we found out more about it. We don't have any conclusive knowledge of cause and effect, just educated guesses. The pilot was a young CFI giving a ride in the Ercoupe owned by a young woman (his girlfriend, I think) to whom he'd been giving lessons. On the catastrophic flight, he was giving a ride to the airplane owner's sister. The CFI pilot was known to do aerobatics in the Ercoupe - something you MUST NOT DO. We don't know if the accident flight involved aerobatics or not but we don't know why the aircraft would have fallen apart as it did unless it was doing aerobatics. The investigators did find some corrosion in the center section spar and cited it - it's possible that the plane wouldn't have come apart without that corrosion. The Ercoupe was originally developed under the old CAR regulations which allowed aerobatics (along with most other aircraft). Under the new CAR regulations, as a "normal" category aircraft, it is not allowed aerobatics. The Ercoupes should NOT be used for aerobatics! They are sleek enough that they gain speed VERY quickly when the nose is lowered. I wouldn't ride in a Coupe doing aerobatics unless Bob Hoover is the pilot. A pretty fair number of Ercoupe owners got the rivet by rivet sonic inspection of the center section following the optional service bulletin that was issued as a result of that crash. None found any aircraft threatening corrosion. (That had been culled out of the fleet via the earlier center section inspection AD.) A very few of those rivet by rivet sonic inspections found a few bad rivets which were easily replaced. So, in summary, I would make ABSOLUTELY sure the wing and center section inspection ADs were properly done. (No Ercoupes have ever been lost in flight due to this corrosion but some were grounded, a few beyond economical repair, due to corrosion found in these inspections back when they came out.) The fuselage corrosion inspection and confirming that the wing and center section inspections were properly done are essential to a good pre-purchase inspection. And, most importantly, I WOULD NEVER do aerobatics in a Coupe. Ed
