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Incomplete data in LSA Aircraft Operating Instructions

Posted: Wed May 23, 2012 10:17 am
by drseti
Here's a revealing report from the NTSB accident database. This was a fatal in an Evektor SportStar five years ago:
The investigation disclosed that the airplane was over the certified gross weight at the time of departure for the accident flight. A review of the Aircraft Operating Instructions provided by the manufacturer, revealed insufficient data to accurately calculate the effects of density altitude on the performance of the airplane for takeoff and landing. The manual also lacked sufficient data to calculate the fuel burn of the airplane for any altitude higher than an international standard altitude of 2,000 feet. This additional information is not specified as a requirement by the current ASTM consensus standards. Density altitude at the time of the accident was calculated to be 7,800 feet.
I can confirm that the AOI is pretty sketchy in terms of performance data at different altitudes. There are a whole bunch of charts required in the POH for certified aircraft that just don't show up for most LSAs. The manufacturers generally have the takeoff and landing distance data available for varying conditions, but the ASTM standard does not require them to include it in the AOI. Pilots, owners, and instructors can (and should) request this information from the manufacturer, and not rely solely on those minimalist AOIs.

Posted: Wed May 23, 2012 10:34 am
by zaitcev
What is your position on the unofficial testing such as that done by the U.S. distributor of CTLS for high altitude performance? Assuming they would share the data with customers, about which I'm not certain. Is it useful, or should I undertake my own rigorous testing upon delivery?