OK...here's a version of that page that isn't so small.Originally Posted by Bill Berson
As can be seen, the 2015 GA survey assumes that, out of 31,765 registered homebuilt aircraft, that 21,195 are active.
But let's look at a little history. The 2010 GA Survey produced an almost identical number of active homebuilts....21270. But the 2013 GA Survey showed only 17,503 active homebuilts. So, according to the GA survey, almost three thousand homebuilts quit flying in the 2010-2014 timeframe.
What ELSE happened during the 2010-2013 timeframe? The FAA re-registration effort. Where, if you owned an airplane and didn't renew the registration, the FAA removed your plane from the rolls.
OVER TWENTY PERCENT of the homebuilt fleet was removed from the registry in this process....about 7800 planes.
My guess is that is the vast majority of those 7800 aircraft were already inactive. Yet by the official FAA survey, roughly 2700 of them were planes that were active and flying?
What happened? Simple: The GA Survey was incompatible with the administrative changes to the registry.
The GA survey works by sending out hundreds of surveys to registered aircraft owners. Part of the survey includes recording how many hours your plane flies each year. If six out of ten returned surveys state that the airplane flew in the previous year, that means that 60% of the fleet is active. If there are 30,000 registered airplanes, the survey multiplies that number by 60% and announces that 18,000 of the registered aircraft are active.
However...not all surveys are returned. In some cases, it's just people who don't like replying to the government. In others, of course, the plane or its registered owner no longer exists. Non-returned surveys aren't factored in.
And, of course, the vast majority of the planes removed from the FAA rolls DID not return a survey. So these weren't counted either as active or inactive.
But what happened, of course, is that the NUMBER of airplanes decreased. So the total registered aircraft drops from 30,000 to 25,000... and 60% of that 15,000. So the number of active airplanes takes a hit.
I'm not arguing with the process the GA survey people use. I think it's about the only way to do it, and in normal circumstances, it's fine.
We *know* that the GA Survey people recognized what the re-registration effort did to the quality of their results. You'll note they didn't publish their results the first year of the re-registration effort ("The 2011 GA Survey is not available and data will not be published. ") So they know the results were ****ed.
Sadly, no one else does. And there are people making decisions on that bad data.
Take, for instance, the homebuilt accident rate. In 2010, there were 188 accidents for 21,270 active aircraft. About 0.88%. There were almost an identical number of accidents in 2014... 184. But the number of active aircraft had dropped to 18,873. So the rate shot up to 0.97%. That's an apparent 10% increase in the accident rate. And people did get upset, even though in reality, the number of active aircraft had actually increased (4,000 new homebuilts added between 2010 and 2014).
Ron "I told you not to get me started" Wanttaja
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