The crash of the Hummel UltraCruiser earlier in 2009 demonstrated
the integrity of the wing connection to the fuselage. The wing
in flight. The pilot reported a loud bang. He then saw the
wing fold. He blacked out. Other reports place the aircraft at 50
to 75 feet from
the ground. The crash occurred during the 3rd circuit. Additional
reports indicate the failure was at the wing root.|
Note: I am not identifying the people until permission is granted.
I received the following report on the pilot, "His wrist was pretty bad and also his left foot. They have put a pin in his wrist and are letting the swelling go down from his foot to fix it. He will likely be in the Hospital for a few more days. He is in good
spirits though and will be taking a few months off to recover" [w]
Links to news report
cnews ... Pilot survives ultralight plane crash
Correction:Immediately after the accident, I was approached by an operator at the airport for comment. My first conclusion was incorrect. [S. Steve Adkins]
"The piece that you thought was the spar cap in photo 1639 is one of the fuselage side stringers that was bent into the spar. I bent it out of the way for some of the other pictures." [w].
"We think that the 6061T6 material is the side rail not the spar cap. Since there are no holes in the top [as would be true for the spar cap]. That is not to say that the spars are correct but we can't tell from the photos. We believe, even if the spars were 6061T6 it should not have failed unless there is some other major construction issues." [m]
The wing spar appears to have been built out of the correct material.
Photos from the Hummel Aviation Website during stress testing:
Interior The center carry-thru support on the right side buckled under compression.
Full Series of Stress Testing Photos
Material Testing performed by Steve Adkins and Dale Johnson
Note: Right wing moved around to facilitate extracting pilot.
This view show the protection provided by the structure.
|For comparison ... test setup at Hummel Aviation:|
The center carry-thru support on the right side buckled under compression.