Lies, damned lies & Statistics

[PJB]

Just read the report and it makes for terrible reading. The AAIB should be congratulated for their efforts in the research and also the obvious push back to merely write it all off as “pilot error”. It also for the purposes of this thread demonstrates that simple narratives or labels of fixed wing pilots become just that (simple). Gyroplane engineering and flight dynamics have been under appreciated forever and perhaps - certainly if the CAA remain faithful to the AAIB - we might gain traction. Students, qualified pilots and instructors don’t know what they dont know.

 

[Mike G]

While updating my spreadsheet I discovered another error
I had counted the Magni M16s twice because in the AAIB website they are sometimes "M16" and other times "VPM".
Here is my updated table of results.

Globally the accident rate in UK comes out at 18%.
There are accidents that never get reported or investigated so that would increase the percentage.
Some gyros were exported and hence de registered so that would decrease the number available to crash which would also increase the percentage.
Some gyros were de registered and re registered with a new registration, that would also decrease the number available to crash.

In conclusion the UK accident rate is probably over 20%.

You can see that the Magni accident rate is lower (15.5%) than the AG accident rate (21.5%), although AG have more than twice the number of gyros imported into UK.

For Abid the Cavalon doesn't come out as badly in UK as in US, in fact it's better than the Calidus and MTO, I wonder why?

Mike

 

[PJB]

Interesting Mike - anecdotally I think a lot of early Cavalons were also rented back to instructors - which also meant that they were on the airfield for the owner / pilot to call upon. What is most interesting about those numbers is that in the entire UK there is less than 100 enclosed gyroplanes and most of those are less than 10 years old. One element of the factory built aircraft that I don't think is yet to be fully know is how well these things age. I would think the GWS should be of great interest to the CAA/LAA post the Scottish accident report!

Is it easy to do the chart on flight hours - which are available on GINFO I think

 

[Abid]

While updating my spreadsheet I discovered another error
I had counted the Magni M16s twice because in the AAIB website they are sometimes "M16" and other times "VPM".
Here is my updated table of results.
View attachment 1162492
Globally the accident rate in UK comes out at 18%.
There are accidents that never get reported or investigated so that would increase the percentage.
Some gyros were exported and hence de registered so that would decrease the number available to crash which would also increase the percentage.
Some gyros were de registered and re registered with a new registration, that would also decrease the number available to crash.

In conclusion the UK accident rate is probably over 20%.

You can see that the Magni accident rate is lower (15.5%) than the AG accident rate (21.5%), although AG have more than twice the number of gyros imported into UK.

For Abid the Cavalon doesn't come out as badly in UK as in US, in fact it's better than the Calidus and MTO, I wonder why?

Mike

Mike
That would directly relate to training hours required then is my educated guess. Average pilot age may also be a factor, but we would have to see if average pilot age in Cavalon fleet in the UK is younger than US or not.

 

[PJB]

I would say unlikely Abid, many older Cavalon pilots, in fact GA in general in the UK is older.

 

[Mike G]

Interesting Mike - anecdotally I think a lot of early Cavalons were also rented back to instructors - which also meant that they were on the airfield for the owner / pilot to call upon. What is most interesting about those numbers is that in the entire UK there is less than 100 enclosed gyroplanes and most of those are less than 10 years old. One element of the factory built aircraft that I don't think is yet to be fully know is how well these things age. I would think the GWS should be of great interest to the CAA/LAA post the Scottish accident report!

Is it easy to do the chart on flight hours - which are available on GINFO I think

Phil what do you mean "rented back to instructors"??

I've contacted the LAA a number of times since our meeting with them when they said they would talk to the CAA and AAIB about the GWS. They seem to be too busy to bother about gyrocopter accidents.

Mike

 

[PJB]

So what is a common practice is Student A buys a Cavalon and gets trained by an instructor. Student A then passes his PPL(G) skills test and from the relationship built with instructor the aircraft is then available to be used by the instructor for training others and a £/hr is returned to the pot. That makes the flying cheaper for the new pilot (as his fixed costs are shared) he gets a little extra for the hours he doesn’t fly and an instructor is available to help as and when

 

[Mike G]

Mike
That would directly relate to training hours required then is my educated guess. Average pilot age may also be a factor, but we would have to see if average pilot age in Cavalon fleet in the UK is younger than US or not.

Abid
here is a scan of the database for UK Cavalons.


You can see that the average age of the crashed pilots is about 60, all with less than 100 hours on type. The problem with the AAIB website is that (unless I've missed something) each case is filed as a document and not in a searchable database and I don't now if "hours on type" are hours on the Cavalon or hours on gyrocopters.

Mike

 

[WaspAir]

I wonder if the average age of the general gyro pilot population is terribly different from about 60.

 

[TyroGyro]

For Fatals, the median age is 59 (the average is 56, pulled down slightly by a cluster of youngsters killed on Ag. Ops. in South Africa by dodgy practices within one company).

 

[Abid]

For Fatals, the median age is 59 (the average is 56, pulled down slightly by a cluster of youngsters killed on Ag. Ops. in South Africa by dodgy practices within one company).

It is hard to relate 59 or 60 to cause or significant contribution for fatal accidents in my opinion. This points to at least on average fatal accidents to have other significant contributory factory then like time in category and class, recency, training etc.

 

[TyroGyro]

It is hard to relate 59 or 60 to cause or significant contribution for fatal accidents in my opinion. This points to at least on average fatal accidents to have other significant contributory factory then like time in category and class, recency, training etc.

Agreed. I doubt the median/average age of those involved in fatals is significantly different from those not involved in fatals...

Time is far more significant. The following chart is based on more than half the total fatals, where gyro hours are definitively known.

 

[Abid]

Agreed. I doubt the median/average age of those involved in fatals is significantly different from those not involved in fatals...

Time is far more significant. The following chart is based on more than half the total fatals, where gyro hours are definitively known.

Looks like a significant number is 100 hours and then 250 hours in gyroplanes. The fatals in South Africa for that company Xsit, those just seem asinine. I would not count them. Cannot take a 20 hour trained pilot in category/class and expect them to do crop spray type of application in hilly area. What a stupid idea in any aircraft type. Those operations require 100's of hours of experience and specific training flying low to do safely. You aren't becoming a gyroplane pilot today and doing agricultural work in 2 months unless you have a death wish.

 

[TyroGyro]

Looks like a significant number is 100 hours and then 250 hours in gyroplanes.

hours
<250 84%
<200 80%
<150 75%
<100 63%
<50 41%
<25 20%


The median hours for dead pilots is 74 hours.

 

[PJB]

hours
<250 83%
<200 80%
<150 74%
<100 61%
<50 39%
<25 17%


The median hours for dead pilots is 74.5 hours.

On the basis our PPL(g) requires 40 hours if you are a new pilot or 20 if an existing of training that is worry isn’t it? I think I’m right in saying that the last two fatal gyroplane accidents in the UK were with student solos.

 

[TyroGyro]

On the basis our PPL(g) requires 40 hours if you are a new pilot or 20 if an existing of training that is worry isn’t it? I think I’m right in saying that the last two fatal gyroplane accidents in the UK were with student solos.

Yes, but unrelated to hours? Rotor head failure, and a medical problem (aged 79, the oldest pilot in the dataset).

My figures are global, which will include some jurisdictions which require far fewer than 40 hours, and some of the dead were crazies on unauthorized flights, intoxicated, etc...

 

[TyroGyro]

The fatals in South Africa for that company Xsit, those just seem asinine. I would not count them.

That's why I offered the median (59), which ignores outliers.

 

[Mike G]

I wonder if the average age of the general gyro pilot population is terribly different from about 60.

WaspAir
I agree, I doubt many guys under 60 have 100+grand to spend on a toy, they're too busy paying off the house and kids education. If your under 40 with that sort of spare cash better buy a Ferrari you'd have a wider choice of women.
Mike

 

[Mike G]

Yes, but unrelated to hours? Rotor head failure, and a medical problem (aged 79, the oldest pilot in the dataset).

My figures are global, which will include some jurisdictions which require far fewer than 40 hours, and some of the dead were crazies on unauthorized flights, intoxicated, etc...

Tyro
The rotor head failure was most likely fundamentally due to low hour student mishandling.
There may also be a design/material choice question but since all the other Cavalons of the same generation aren't falling out of the sky I'd say that this was an hour's/training issue.
Mike

 

[PJB]

Tyro
The rotor head failure was most likely fundamentally due to low hour student mishandling.
There may also be a design/material choice question but since all the other Cavalons of the same generation aren't falling out of the sky I'd say that this was an hour's/training issue.
Mike

Agree with that but never the less we have a generation of Gyroplane accidents with no rotor head failing - then a new design and 2 in two years. Sure there maybe mishandling but then the recovery from unusual attitudes is an excerise that accepts things get mishandled from time to time. Was that in the process of happening and the rotors detached? I don’t know. Neither does anyone else. The AAIB report highlights fundamentally some flakey practices in training, regulation and manufacturing. It will be interesting what is done with the safety recommendations. The AAIB may not be Gyroplane subject matter expert but they are a fresh pair of eyes with huge aviation experience, engineering knowledge and a professional and diligent attitude. They, reading this report, were right to ask the questions being asked.