According to the pilot/owner/builder of the Minicoupe, he conducted taxi tests, and then a final engine run-up and flight control check prior to takeoff on the airplane’s second flight near Baltimore.
After rotation, the plane reached approximately 3 feet above the runway when the nose dropped, and application of full up elevator had no effect. The airplane hit the runway nose first, which resulted in substantial damage to the firewall.
This was the identical outcome as the first flight several months prior.
An FAA inspector estimated that the builder had added about 63 pounds with his modifications to the original airplane plans.
The pilot performed the weight and balance on the airplane using bathroom scales and stated that there were no mechanical deficiencies that would have precluded normal operation of the airplane.
His NTSB Form 6120.1 Operator/Owner Safety Recommendation was: “Re-weigh aircraft with calibrated scales to determine weight and balance. Fix apparent nose heavy aircraft with appropriate movement of the battery or additional weight in the tail section.”
The NTSB determined the probable cause as the pilot/owner/builder’s improper weight and balance calculations, which rendered the airplane uncontrollable in the pitch axis.
NTSB Identification: ERA14CA408
This August 2014 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.
Now that I’ve had a look on a mini coupe airplane flying on utube I suspect my first post to be right. I hope the builder is reading this? Some sage advice. Don’t
Build a plane heavier than the designer designed because you think it’ s better.
Books have been written on this subject alone. But now that you have put it on a diet. Get rid of as much weight as you can. Now get a lot of practice with stalls with an instructor in a 150. Do a weight and balance for everything get it wright your life depends on it. Calculate the new stall speed at your take off weight add 15-20 mph to that for take off. Preflight it like your life depends on it. Don’t forget the gas.
Fly
Another good reason why amateurs building airplanes should limit them to models.
Wiley Post made just such a fatal mistake with the nose heavy pontoons that were installed on his hybrid aircraft that when nose down into the bay when power was lost on take off taking both his and Will Rogers life.
Maybe the elevator is not large enough, or in the best location to give positive control!
“This was the identical outcome as the first flight several months prior.”
And what if anything did he learn from that first flight? High speed taxi tests should have indicated a problem had the speed, amount of elevator deflection required and runway distance needed to raise the nose been noted and compared to known data.
maybe he just stalled the airplane 3 feet off the ground leaving no time for recovery. If you have the courage to fly the airplane next time keep the speed up and go for 3000feet then pull back. I recommend some lessons and time flying a tested airplane to get rid of the yellow streak you have now. work on stalls.
use bricks to balance the airplane they work fine evertime no error.
FWIW I’ve seen the ‘bathroom scale trick’ used in years past by some small (read than one guy) A&P shops. That, and other corner cutting have kept me from taking my aircraft to those “maintainers”. This builder probably saw the same bad practice used by a “professional”. It’s another reason why owner assisted annuals (where the owner is watching with a critical eye) are a good idea.
John, I agree that there are some shady maintenance facilities out there, but not all one man shops are bad. I strive for excellence in every aspect of aviation maintenance and I have certified scales too! I know of some facilities that have several employees with a high overhead that turn out some pretty crappy work! A friend just used one of those shops for a tire change on a C182, they installed the inner brake lining backwards so it ruined the brake disk.
I’d like to know how much the aircraft would have weighed without the 63 additional Lbs. If it was around 1100 Lbs then the additional 63 Lbs would have added approx 6% and if it was forward of CG which is what is suggested then that would be dangerous.
My bathroom scale is always lying to me. Why would he use uncalibrated scales for these critical calculations and jeopardize his life.
Once again. You can’t fix stupid.
Calibrated scales are expensive and not always readily available when completing an EAB project but that is still no excuse for not putting in the time and effort to get a proper W&B on a new aircraft, especially one with significant changes from the plans.
To that I add: The definition of Insanity is to do the same thing over and over and expect a different result. This guy was crazy to think it would work any better on the 2nd flight then the 1st if no remedial steps had been taken.
Try again! Maybe it will work the third time??