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Kyrilian,
Your points are well taken and we need to address these issues with the FAA-- it is their data that makes this task impossible. They use our tax dollars to send us those triennial reports that we must fill out lest we lose our privileges and the darn data it produces is about worthless.
Jeff
-----Original Message-----
From: Kyrilian Dyer <kyrilian_av@yahoo.com>
To: lml@lancaironline.net
Sent: Sun, 9 Nov 2008 6:10 pm
Subject: [LML] Re: Safety in our Community of Lancairs
Jeff,
I agree with your sentiment below, but I don't believe the numbers required to truly make the point are available. The percentages below are useless if we don't know the number of hours flown and the number of pilots in a given group. For instance, in your pie chart of accidents by certificate, you show that only 1% of Lancair accidents occur with student pilots. Are student pilots the safest?
A true comparison of private and commercial (or ATP) pilots based on these limited data is impossible to make. There are two unknowns here; the number of Lancair pilots with a private, commercial, or ATP certificate, and the number of Lancair hours (not to be confused with total hours) the pilots in each of those groups fly per year. Do private and commercial pilots fly the same number of hours each year in Lancair aircraft? Even if we know the ratio of private to commercial and ATP pilots in the Lancair community, do we know the number of hours that each group flies. And the total number of hours is useless--we need Lancair hours to compare the accident rate in Lancairs.
Let's compare a bunch of ATPs who fly a few hundred hours as jet captains but only fly five hours each in Lancair aircraft each year with private pilots flying their Lancairs a hundred hours each year. Say we look at a group of a hundred private pilots that had twenty accidents and a group of ten ATP jet pilots that had one accident in the same period. If we didn't know how many pilots were in each group or how much they flew we'd say that the private pilots were twenty times more likely to have been involved in an accident. However, if we assume the above flight rates (in Lancairs), the ATP group would have an accident rate ten times greater.
ATP: (1 accident / 10 pilots / 5 hours per year) = 0.02 accidents per hour per pilot
Private: (20 accidents / 100 pilots /100 hours per year) = 0.002 accidents per hour per pilot
Obviously, the numbers above are simply hypothetical, and I would expect, far from reality. However, it simply shows that without knowing the real numbers, it's impossible to compare accident rates.
You also bring up the relative number of pilots in each group (35% of the US pilot population is comprised of private pilots). But how many in each group fly GA? While many airline pilots fly GA, I'm sure there are many that haven't been in a light aircraft since they were private pilots. I work with a bunch of very highly qualified experimental test pilots, most with ATPs and thousands of hours and all with military backgrounds. Only a small few fly light aircraft.
So are student pilots the safest? I doubt it. Let's keep training, and try to get those hours in type higher (somehow).
Cheers,
- Kyrilian
--- On Sat, 11/8/08, vtailjeff@aol.com <vtailjeff@aol.com> wrote:
From: vtailjeff@aol.com <vtailjeff@aol.com>
Subject: [LML] Re: Safety in our Community of Lancairs
To: lml@lancaironline.net
Date: Saturday, November 8, 2008, 10:10 AM
Kevin,
I am not saying anything. I am just doing the math. Once I have finished the math I will let everyone know... I did address the hour thing in the other graph. Put the two together and you have a picture. Private pilot + low time in type= higher risk of accident.
I agree that training reduces accidents. As I said earlier in my ten recommendations to become a safer pilot is if you are going to spend the money training you might as well get a new rating. ;)
Jeff
-----Original Message-----
From: Kevin Stallard < Kevin@arilabs.net>
To: lml@lancaironline.net
Sent: Fri, 7 Nov 2008 5:37 pm
Subject: [LML] Re: Safety in our Community of Lancairs
Jeff,
>While Private Pilot certificates comprise 35% of total U.S. pilot population.
>Private pilots account for almost 55% of the Lancair accident population and 48% of the GA accident population
I think you are trying to say is “If you only have a Private Pilot certificate, you are more likely to have an accident.” And that you probably mean to imply
that if you hold some other advanced rating, that you have a less chance of having an accident.
The propblem is (at least for me) is that 100% of GA accidents are caused by, well, pilots, and half of those accidents (or thereabouts) are caused by folks with higher ratings than a private pilot (according to your numbers).
I’m not convienced that a rating is the thing that is indicative of the likely hood of an having an accident, however, I think that the amount of practice and training are, and unfortunalty ratings don’t accuratly reflect this quantity. However, a logbook usually does. Maybe that’s were we need to look.
Kevin
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