90 days/28 days experience - in accident reports

[rans6andrew]

Is there anything significant about the 90 days and 28 days flying experience quoted in accident reports?

I can sort of see 90 days cropping up as this is the currency requirement for carrying passengers, 3 landing in the recent 90 days.

What is the point of the 28 days experience quote?

I was thinking of this, today, when I was on my way to the airfield. My logbook shows that the last time I "commited aviation" was on September 11th. That is 211 days ago. It went all right, thanks. It seems that once you have it, it is like falling off a bike! You never forget. After landing I walked away and the aircraft can be used again. Bonus.

[Jonzarno]

Artur Rubinstein who is acknowledged as one of the greatest pianists of all time put it like this:

"If I don't practise for a day I know the difference; if I don't practise for a week, the critics know the difference; if I don't practise for a month, the public knows".

Flying skills, especially the more advanced skills associated with instrument flight and fast aircraft, atrophy surprisingly quickly. For me, at any rate, even though I fly about 250 hours a year, whenever I don't fly for a few weeks when I go away on holiday or my plane is in for annual, I'm always grateful that I don't have a critic or a member of the public with me on my first flight. :O:8

[Genghis the Engineer]

I find them a fairly useful measure of recency and have adopted them in my electronic logbook - it flags to me that I need to take care if I drop below 3 hrs in 28 days, or 10hrs in 90 days (my choice of values, which seem about right) and at that point I'll at the very least go and spend some time either on my own or with a friendly grownup refreshing the usual basics of circuits, PFLs, stall recoveries, check fluency, RT and the like. I really should do the same with instrument flying like Jon does as well.

I really hope Andrew that you're playing devil's advocate here as at 211 days out of recency I'd be looking to refresh on the manuals and checks, and probably spend some quality time with an instructor. Mind you, I've only got a couple of thousand hours and a CPL - you may have a lot more experience and training than me and not need to be as cautious as myself and Jon.

G

[megan]

My logbook shows that the last time I "commited aviation" was on September 11th. That is 211 days ago. It went all right, thanks. It seems that once you have it, it is like falling off a bike! You never forget.Far better man than me Gunga Din. Coming back after two weeks leave I could notice the slight loss in handling skills.

[cats_five]

For a variety of reasons I hadn't flown since early May last year. Had check flights with an instructor and went for extra flights with him to sharpen up my landings - there is only one go at those in a glider.

I was allowed to fly solo again after the first set of flights so I've done a little of that as well. Now I've got it right in both almost no wind, in some wind, and when there was massive sink in the circuit, and on another day when there was lots of windshear in the last few seconds I feel equipped to start flying my own glider again.

To a degree it is like riding a bike, but IMHO what goes is what you learnt most recently so for a low hours glider pilot just about everything, for a more experienced pilot the co-ordination remains, but speed control might not be so good, plus adapting to different conditions, spot landings, and airmanship when other gliders are around.

[Genghis the Engineer]

In my experience, basic handling skill isn't usually what's lapsed most when I've not flown for a bit.

RT and following of procedures are usually the first to go - I spot myself making small mistakes, or getting into a bit of a muddle over some complex RT if I've not flown for a bit. The other biggie is capacity - if I try to do something fairly complex: say a DME approach, or flying a PFL into a smallish field, I can fairly easily get overloaded and less able to cope with anything additional coming my way.

John Farley wrote an excellent chapter on this in his book "A view from the Hover", which also described the importance in his mind (and I'm certainly not going to say that JF was wrong!) of also making sure if you fly relatively limited hours or usually in a similar pattern of taking the limited time you have to rehearse the most important skills. He advocated constructing a personal checklist to ensure that you've done various things that matter to your flying within a reasonable period of time.

I don't formalise it quite as much as he proposed, but certainly I think that his arguments are right. For me RT in controlled airspace, PFLs, stall recognition and recovery, and flying accurate (IFRish) height and speed occasionally are the things I most carefully watch. I'm sure that other people on self analysis would identify other things that matter more to their flying.

G

[Jwscud]

They are also to do wit the legal limits imposed on Professional pilots - maximum 100h in the last 28 days, and a requirement for 3 takeoffs and landings in the last 90 days.

Hence I assume (though assumption it is) they became part of the standard format for reports.

[Chesty Morgan]

Yes, I think the 28 days is used as an indication of how busy you've been with, for instance, fatigue implications, rather than how current you are.

[9 lives]

Self recognition of the affects of a piloting absence are an important beginning. Those first few refresher flights should either be supervised by a current qualified pilot, or based upon a lot of experience and self awareness.

Two of the more skill and technique demanding types of flying are water and ski flying. As it is here in Canada, your opportunity to maintain currency is seasonally limited - and global warming is affecting that! That first float flight of the season, I pay very close attention to myself. Happily, this year, I enjoyed a float flight in Norway two weeks ago, which was a beginning of my having to give seaplane rating training later this month.

The other aspect I find worthwhile, is that I practice emergencies a lot, and in different types of aircraft. I meet many pilots who fly the regular hamburger runs, but when it comes up for discussion, have not flown a forced approach, nor unusual attitude recovery, in recent memory. Currency is one thing, breadth of currency is another....

[Jetblu]

I do agree that currency is good, but I'm not so sure if 211 days absence is such a deal breaker regarding competence and safety, dependable upon experience.

I was absent for 573 days, jumped in, 4 circuits, asymmetric engine out, restart and in for the procedure at Southend. Probably the best landing that I've done since. I was maybe a little rusty than my usual, but nothing significantly noticed.

[Maoraigh1]

I lose skills quickly. I've only once gone 200 days without flying, and my check flight started very poorly. I keep current. I know some group members who can keep their skills over almost a year without flying, although total time is only a few hundred hours.

[blueandwhite]

Go flick through the AAIB light aircraft incidents and it is very rarely the guys who fly often and almost always very little time in the last 28 days / 90 days. Infact it is one of the first items I look at on the report with the typical ground incident / buggered up take off or landing / approach.



Has anyone seen any proper research on any relationship between currency and accidents?

[rans6andrew]

Actually, I am not playing devils advocate. After a "risk analysis" I opted to go ahead and fly it by myself. I based my decision upon the following.

I don't perform at my best with someone watching over me. I hate the biennial flight with the instructor although I admit that it is beneficial in that it forces me to react to sudden situation changes and practice engine failures. Yesterday I didn't need the pressure of being observed, I am fairly self critical and make some effort to keep my skills up normally.

The aircraft is a 3 axis microlight and is relatively easy to fly.

I have been "less than current" a few times before for viarious lengths of time. I missed two or three months after hospital surgery, twice, and nearly five months while the aircraft was repaired following storm damage. The first flights went well, including the landings, in all three cases.

The weather conditions were good and the wind was forecast to be in a good direction for the strip. In the event the wind was light and variable so the landing wouldn't necessarily be in the expected direction or shortened by the wind speed. I judged it was still acceptable.

I was well rested and in the right frame of mind for flying. I see that there is another thread about flying just to keep a licence valid whether you want to fly or not. I don't do that as I find it counter productive. My mind was ahead of the aircraft from the preflight until the drive home.

The aircraft is mine. Nobody puts me under pressure to take a check pilot for insurance purposes after 28 days (there it is again, 28 days!). If the aircraft is "US" nobody else is inconvenienced.

After considering the above I decided that the biggest thing playing upon my mind was the landing back at the home strip. The strip is not too long, 380 metres with trees just before the threshold when the wind is westerly. It is not too wide at 12 metres so crosswinds can be a bit demanding. Another issue is that it is not completely flat which makes it look much shorter from when you turn final until you come to a stop. It is on the top of a hillside and suffers curl over when there is any south in the wind, which there has been regularly recently. Not yesterday though.

Whenever my currency is low or the conditions for getting back into my home strip look to be challenging I do what I did yesterday. I fly to a nearby strip which is almost exactly twice the length and twice the width and is the same orientation and I shoot a few touch and goes until I am really comfortable and hitting the numbers. Then I return to the home strip relaxed and ready for it.

I was pleased with my performance yesterday. One overshoot which I caused by being slow to notice being so high that I couldn't side slip enough to rescue it. The slab sided Rans S6 would practically drop out of the sky when slipped but the current aircraft is a bit more slippery and doesn't go so steep. Then I did two good approaches and greaser landings. I headed back to the home strip and, after doing a fly by to check the windsock (the wind was a bit variable all day), completed a tidy circuit and a good landing.

I am still not ready to be taking passengers (I don't want the responsibility or the distraction) but I am comfortable to go on my own again, soon.

[blueandwhite]

Must admit I have no idea and fair point well made although I'd hazard a guess there will be a corolation..


Well I'm glad going solo at it you seem to have made lots of very sensible pragmatic approaches to flying out of currency. I've seen countless private hirers well out of currency in unfavorable conditions with pax determined to go. I will always stick with going with an experienced FI is best and I'm sorry to hear you hate the bi-annuals.. sounds like bad experience with instructors. I always try my best to make them relaxed and fun but testing and informative.

The first bit seems to be a reply to my question about research. The second seems to be in reply to another. But I was also wondering if there was any evidence to indicate that the two yearly flight with an examiner has any effect on safety.

[rans6andrew]

I don't have any particular gripe with instructors, I have never been comfortable with anyone looking over my shoulder whatever I am doing. It's just the way I am.

I do have an issue with the biennial flight requirement though. When I first got my NPPL(M) there was no need to do the hour flight, licence reval was done by a signature in your logbook, by an approved licence signer, who knew you well enough to know that the hours claimed were correct. This boiled down to buying a pint at the club meeting for a fellow pilot who flew with us on our annual trip touring France. The cost was less than a fiver. Then without doing a proper impact analysis someone who didn't represent microlighters decided to vote for a change of requirement. This now costs most of us £100 plus for the reval flight with the instructor. I would be interested to see whether it has brought any improvment in the accident stats. It is barking. The folk who still hold the old PPL(m) licence still do it by the pint in a pub method. Strangely, they have not all crashed and burned.

[Genghis the Engineer]

I doubt that the two-yearly flight with an examiner has had any real safety benefits in the UK.

The pilots who are prepared to learn, will learn anyhow and find those opportunities. Those who think it's pointless, will do the minimum to tick the box.

The American system that requires a minimum standard of flying to be displayed every 2 years seems massively more rational to me. But, it was politically unacceptable in Europe.

Surprising really - you'd have thought that the Americans would have been the people to fight for freedoms at the expense of safety, not the Brits.

G

[Genghis the Engineer]

I've been flying for 8 years and teaching for more than 3 and i look forward to doing flight tests / reccurency training with the CFI etc to have a chance to learn more and polish up parts I may be overlooking.
Bigger numbers for me, but I agree - *however* I've also a lot of sympathy with those trying to do their flying on a budget, or in a type of aircraft for which instructors are hard to find. For those people the cost and inconvenience can be large.

It's one of the reasons why the inexpensive CRI course is so good as, for example, it allows the relatively affordable existence of LAA coaches and/or instructors within syndicates. Certainly I'm in a couple of syndicates where part-time FIs and CRIs do biennials for a coffee.

Which is a valid point - Andrew, why don't you use the LAA coaching scheme for your biennial? It's for expenses only, and you'll get an instructor familiar with your class of aircraft, doing it purely because they enjoy instructing.

G

[rans6andrew]

G the E, I did enquire about the LAA coaching scheme with reference to reval of my NPPL(M) in 2014. I forget exactly what happened but I think Turweston couldn't point me to any LAA coaches able to help.

Maybe you know who I should be talking to? I am in the Reading area but obviously I can fly to wherever I need to be for the flight.

The time before, in 2012 was just after my aircraft was damaged by a storm and I was obliged to go to a flying school and do the flight in a "strange" aircraft at great expense.

It isn't just the expense that annoys me it is the imposition of the system after working with the old PPL method for so long. If it had been imposed in the name of safety it would have been applied to the PPL(m) licence holders at the same time. It was done, I'm told, to simplify paperwork across the NPPL types. The people representing the microlighters on the NPPL committee were not in favour of the change but some bod from the LAA (who at the time represented a tiny tiny fraction of the NPPL licence holders) railroaded it through without doing the necessary impact assessment.

[Genghis the Engineer]

The chap who posts as Cookie on the Flyer Forums is head of the LAA coaching scheme, and doesn't mind being contacted that way.

Regarding biennials and legacy NPPL(M) holders - the powers that be tried extremely hard to impose biennials on them, and the BMAA successfully fought them off. Entertainingly, the BMAA Chief Executive who did that, now works for the CAA. I think that they decided to turn a poacher into a gamekeeper, and he went to subvert them from within. Who succeeded, I'm not quite sure.

It was imposed for safety purposes certainly - but as I've said already, in my opinion badly done as in reality it has not been done in a way that mandates minimum flying standards to be displayed. I'm glad to say that any pilot I've flown with who was (in my opinion) dangerous has accepted the point and the need for some additional training anyhow.

If you need a biennial - I live half an hour's drive from Reading and don't mind doing a flight with you for a bacon sandwich so long as it comes with a mug of tea as well. I know microlights well, although freely admit to not being deeply familiar with the S6 - I have flown one and have been testing a SkyRanger recently, which is in the same ballpark, flying-wise.

G

[flybymike]

I will always stick with going with an experienced FI is best and I'm sorry to hear you hate the bi-annuals
Biennials are bad enough never mind biannuals

[flybymike]

The CAA did a safety review in 2007 following the introduction of the new JAA rules on biennial instructor flights, 90 day rule, annual MEP tests etc which were introduced in 1999/2000.

The review concluded that they had brought no improvement in safety statistics.

I used to keep a link to the paper in my bookmarks but alas it is now redundant following the revamp of the CAA website and I can no longer find it.

[flybymike]

I doubt that the two-yearly flight with an examiner has had any real safety benefits in the UK.
See above.
(It's only an instructor flight unless rating expired of course)

[Sir Niall Dementia]

I've got so used to 6 monthly sim checks and OPC's on two different types, plus two annual line checks and safety certs that I just carry it into my private flying and twice a year fly with an instructor for a brush up. I always learn something and always enjoy it.

My employers have a policy that after 2 weeks away a pilot goes to the aircraft early and just quietly re-famils with his office. A month away would mean a line flight under supervision and 90 days a brief check with TRE/IRE and those rules are for pilots flying 500-700 hours a year.

Back to the OP: the 28 day and 90 day stats were for commercial ops to show fatigue or lack of currency. When I appeared in one of those reports me (the P1) on the flight had 3 700 hours, the P2 (who was the company Chief Pilot had
21 340 hours of which 18 900 were on type!

SND

[DeltaV]

The main thing that hacks me off about the biennial flight with an instructor is that, by definition the aircraft must have at least two seats. So I am forced to fly something that bears almost no resemblance to my own machine, other than it has wings and can fly. That might be OK if it was something unusual or exciting but invariably its a C152 or a PA38.

I believe the American biennial, though, can cope with that allowing the single seat pilot to fly their own airplane with observation and instructions by radio from the ground.

[blueandwhite]

I doubt that the two-yearly flight with an examiner has had any real safety benefits in the UK.

The pilots who are prepared to learn, will learn anyhow and find those opportunities. Those who think it's pointless, will do the minimum to tick the box.

The American system that requires a minimum standard of flying to be displayed every 2 years seems massively more rational to me. But, it was politically unacceptable in Europe.

Surprising really - you'd have thought that the Americans would have been the people to fight for freedoms at the expense of safety, not the Brits.

G

I agree with your thinking here.

But it was supposed to be a safety issue. Why can't we have decent legislation?

I flew today after 100 or so days. I was a bit behind the aircraft, but I don't think an instructor sitting beside me would have made any difference.

[Genghis the Engineer]

I think that if, as stated, the 28 & 90 day recency figures were introduced to indicate fatigue - this shouldn't devalue their additional use to indicate whether somebody is in sufficient flying practice.

But it was supposed to be a safety issue. Why can't we have decent legislation

Because when that was tried, it was fought against tooth and nail by the representative organisations of pilots who considered it an unncessary and unwanted imposition.

G

[rans6andrew]

G the E, I might take you up on your kind offer later in the summer, when I am due to be spied on again. Where would you recommend going for a decent breakfast? It doesn't matter if it takes over an hour if the food is good. Also, the Rans went to a new home some 5 years ago, I am enjoying a Foxbat A22L these days. Still microlight, high wing, side by side, 3 axis, good viz, nothing to worry about.

If the change to the NPPL(M) reval can't be shown to have improved safety, can we go back to the old system? If not, why not? It seems that the only people getting benefit from the change are the microlight instructors.

[Genghis the Engineer]

Possibly better to pick a destination for its learning benefits rather than the quality of the catering? But anyhow, so long as I had the manuals a couple of days in advance, I'd have no issue doing a biennial flight in a Foxbat. Just drop me a line a few weeks before so that we can both plan for it and try and give you the greatest learning benefits from the flight.

I would say that rather than "can we go back to the old system ", the best question would be "what would give us the greatest safety benefit for the least cost and inconvenience? ".

G

[Sir George Cayley]

When I were a lad I got into a vicious circle over checkouts for PPL hire at my club. They used to have a pragmatic approach and so the CFI would allow some renters a bit of leeway recency-wise.

When that changed to six weeks and then to monthly for all, it coincided with a cashflow problem for me.

I could just afford 12 hours a year on the cheapest a/c on the fleet, so every time I turned up for a booked 1 hour solo hire I was check rided. I never had any problems and my notes consistently reflected that. "Good hands" was my favourite comment.

So at the end of the 1 hour check ride the instructor would get out and then express surprise I was following him to the club house. When I explained he had just used up my money I occasionally got a mumbled apology. Seemed like they were told to make money out of the rule blaming the insurance company.

However I was never shown anything in writing to support that.

Now years later, fabulously wealthy with my own aerial carriage I still feel a bit hard done by in view of the number of 'clean' checks recorded.

I support the notion that down time is not necessarily an indication of increased risk but how to translate that into a practical solution escapes me.

SGC

[rans6andrew]

I do hope that you didn't get up at 05:36 (or 04:36 on the original list, Pprune has some bugs in the time display software) just to respond to me!

I am intrigued by the "pick a destination for it's learning benefits". Can you give me some examples? Obviously we don't need to go to Southend for ILS approaches so what have you in mind?

[Genghis the Engineer]

I was up at 5. At 5:36 I was eating breakfast whilst browsing PPRune in Buckinghamshire. At 1400 I was in a meeting in Dundee ! Sadly the Scottish weather was carp, or I wouldn't have been up so early to catch a train, and would have flown myself up. However the upside is that at quarter past five, with my day done, I am now enjoying a pint of good Scottish beer.

For example. ... if somebody is used to flying from big controlled airports with long tarmac runways then one might see value in , say taking them to Popham. On.the other hand, if they are used to non radio farmstrips - they can learn a lot from a trip to Cranfield or a zone crossing through the Southampton overhead.

For example, and always by agreement with the student. The point of a biennial being, arguably, to give someone a chance to review and sharpen their skills in relative safety and comfort.

Similarly, unusual attitudes and PFLs with someone who spends their life impersonating an autopilot on long trips.

And assuming that the pilot is serious about using the exercise to learn something or sharpen their skills up a bit.

G

[Camargue]

the last one is a good point Genghis. many years ago during a biennial at old sarum as the weather was rubbish I suggested we did some IF (I had done the imc equivalent on an air squadron but never translated it to an imc rating) as would be a good refresher

these days due to the nature of my flying, a zone crossing, landing at busy tarmac airfield and using a transponder would probably do me the world of good ;)