Owned or Hire [Archive] - PPRuNe Forums

avonflyer

9th Dec 2009, 22:23

on how much you want to spend (sorry I meant fly - but they are mutually linked). For me, with the amount I fly, it just about works out less costly to hire.

There is also a line of thought that says that renting MAY lead to less potential hassle. The planes may not be so tidy BUT, when you are done, you walk away and dont have to worry about the internal group politics, maintenance or potential for someone bending your share of the metal..

However, the minute you want to regularly fly more than 2 or 3 hours a month, over longer distances and perhaps with overnight stop overs, it appears the equation changes radically. Renting does not make sense.

So I come back to, how much do you want to spend ?

flybymike

9th Dec 2009, 23:02

The first time you get a bill for a new engine you will see the benefits of hiring....

BeechNut

9th Dec 2009, 23:26

ow the flying hours really become expensive since fixed cost+ variable cost/ hrs makes the bill.

True but the total cost does go down in relation to how much you fly. The variable costs (fuel, oil) are in direct proportion to hours flown. The fixed ones aren't of course so the cost per hour goes up, but the total per year goes down. I can fly 50 hours and spend $3000 per year on fuel, or fly 25 and spend $1500, and when you fly less the looming engine overhaul is further out.

So you have to factor in budget, and there's the emotional factor of owning instead of hiring. Hiring can be a PITA especially when there is little in the way of local choice and the local school runs like the monopoly he is. I have to drive about an hour to find another airfield and place to hire.

You may be able to rent block time from a local aircraft owner though. And if you own, it's a way of sharing the costs.

Personally, I own for the reason above: the choice of local rentals. It's expensive, but then what hobby for grown men (and some grown women!) isn't? From what I hear, sailing, motorbikes, sports cars, snowmobiles, and, umm, Tiger Woods' hobby (sorry couldn't resist :rolleyes:), they all add up and except for flying 20 y.o. spam can like I do, their toys tend to depreciate in value over time, some (bikes, cars) like a stone actually.

I've seen guys spend $10k p.a. plus on things like snowmobiles or sailing. I spend significantly less than that per year on my Sundowner. When the price of fuel skyrocketed, I flew just as often, but shorter flights :}

And I get to decide when to fly. No more showing up for a booking and being told "oh, sorry, we sent a guy out on a solo x-country, he has a flight test coming up and the weather was ideal for it...". Yes it did happen. Frequently.

Beech

neilgeddes

10th Dec 2009, 06:58

Seems to me there are more planes to fly than pilots to fly them.

At my clubs at Redhill and Biggin there's generally good rental availability, especially early in the week, and you can book just a day or two ahead. Then, if you find something not quite right with one plane during your preflight check chances are you can take another. If you're prepared to put down some money with your club (and that's been discussed to death elsewhere here) rental prices can be keen.:)

Justiciar

10th Dec 2009, 08:20

Seems to me there are more planes to fly than pilots to fly them

That is certainly true at the moment. In my area at Norwich there is a very nice Warrior (which I am renewing my IMCR on), a Robin (the aerobatic one) and a C172 which spend most of their time sitting about waiting to be flown.

Be wary of figures quoted from across the pond. They are lucking in the cost of flying, but over here the figures are vastly different. Having owned and had shares in a number of aircraft I would say that in pure money terms renting is cheapest unless you are flying a lot of hours.

Of course, there are other reasons to own outright or in a group. Avaliability, the choice of aircraft and control are tha major ones. Hiring something bigger and faster than a C172 or PA28 180 is more difficult due to availability and currency requirements. A good compromise is a non equity group if you can find one. There are a few about - there is one in North Norfolk flying a C172. My own group owned Chipmunk is non equity, but this does not protect you from the impact of serious costs - we are about to write some very large cheques for a partial engine rebuild :{

The other point to consider is that if you own a particular machine you feel obliged to fly it to the exclusion of everything else. Hiring gives you more money potentially to spend (it may not feel that way when the plastic is swiped but it is true) and you can take the opportunity of flying different types. I reckon that for a typical spam can you would not break even under 40 hours per year, possibly more. If you have a budget figure in mind then within that you could do some aeros, tailwheel, floats etc.

If you are determined to buy then consider Permit aircraft. An acquaintance of mine ownes a Rallye which is on a C of A. He is a licensed engineer and does all his own work. Even he finds a C of A aircraft too expensive to operate. They really are the preserve of groups and flying clubs and schools now. With permit you can go from an old Aronca or Cub (not the later ones, which are on C of A) up to one of the modern, cheap to run but expensive to buy kit aircraft like the Sport Cruiser or Pioneer.

Rod1

10th Dec 2009, 08:56

The economics;

If you get a share in a permit aircraft you are looking at typicaly;

1/5 Jodel £3000
£35 per month
£35 per hour

Small risk you will have to pay something extra if the engine fails, but this would mostly be covered by the engine fund if the group is well set up. You are likely to get £3000 for the share when you sell. There are many more similar comparisons but without more info it is hard to quote the right one for you.

Compare the above with the cost of a 152, and decide how many hours you plan to fly.

The practicality;

Main advantage of a share (or your own machine) is availability. You can usually take a group aircraft away for a week a year and it will be normal to take it away for a day at a time. This will allow you to get more from your flying, and you will do more hours. I was involved in several groups from 1991 to 2006, and averaged over 50 hours a year. I could not have afforded to fly that much if I had rented. In that time I also never had to pay “extra” to fix a fault. I now run my own machine, on a Permit.

Rod1

hatzflyer

10th Dec 2009, 09:02

Some people treat aircraft like women, thats why they are ususally reffered to as "she".

I suppose there are various similarities, they both cost a fortune, give you good times, drive you mad, wish you could do without them but love them ,etc.etc.

Some guys say its cheaper to buy them when you need them, that way you get to experience more variety, can walk away when you like, have no ties.

Others rush headlong into a marriage, only to divorce quite soon and pick up a newer model.

The lucky ones find a soul mate and have a life long marriage to a dependable ,relaible , easy to get on with partner that they know everthing about, allways there when you need them, no skeletons in the cupboard.

SO..how do you like your women? :ok:

Justiciar

10th Dec 2009, 09:21

Some wear you out trying to get them started then wonder why you start looking at a newer model :}

The lucky ones find a soul mate and have a life long marriage to a dependable ,relaible , easy to get on with partner that they know everthing about, allways there when you need them, no skeletons in the cupboard.

But with some, no matter how much you spend on them and how much you think you know them they still let you down at the wrong moment :*

hatzflyer

10th Dec 2009, 09:33

Especially if you don't throw the right switches !:O

englishal

10th Dec 2009, 11:48

If I rented in the UK I would have stopped flying here by now.

Because I own, I can take the plane when I want near enough, I can go away for as long as I want, within reason, and I can fly for as long or short as I want. I can alsogo when I feel like it, and don't usually have to worry about coming back late.

For me it is a no-brainer. I own in the UK then go to the USA several times a year and rent something worth 1/2 million $ and enjoy that too.

AndyGB

10th Dec 2009, 12:56

I was like Englishal when I first got my licence, however I did actually stop flying.

When I passed I could only really afford an hour a month and as a result of cancellations etc usually spent part of that hour doing a club currency check. As you can imagine the lure of doing that quickly palled and I decided to take a break, letting my rating lapse.

After 4 years and once finances improved I bought a share in a permit to fly Auster for £3000. This costs me £55 a month and £45 an hour, so the first hour I fly every month isn't that much cheaper than renting. However the second and third hours are less than half the price. Obviously with a CoA aircraft the costs will be higher in order to cover the maintenance costs that a permit aircraft avoids, however it will (probably) be chaeaper than hiring.

To give you an example how this allows you to fly more, I have the aircraft booked for a couple of hours this weekend in order to take my daughter for a flight. If I was to hire this would cost me over £200, which would certainly make me think twice. However £90 isn't such a hit. I pay the standing charge by DD and consider it to be the same as a utility bill, so don't really notice it.

However as others have said, the real benefit you get from owning, be it solely or as part of a group is increased utility. If I want to take the aircraft away for the weekend I can without having to pay for a minimum number of hours, even if I don't fly them. I can just turn up at the airfield and (more than likely) be able to take her up for an hour or two without having to pre-book days in advance. Also, because the aircraft isn't used for training I am not going to turn up to find that it is late back and but that somebody else has it booked immediately after me and so my slot gets squeezed down to 40 minutes from an hour.

Andy

Arclite01

10th Dec 2009, 15:28

Good posts from AndyGB and Justiciar

right on the money.

Arc

Justiciar

10th Dec 2009, 17:43

Rod1 very well summarises the ideal arrangement. A jodel is an old aircraft now but by all accounts a lovely mark (I have not had the pleasure). I did however have a share in a cub which cost a similar amount. There is always the risk of a big hit with an engine replacement but that is a risk to balance up - check any group accounts regarding an engine fund.

IO540

10th Dec 2009, 19:13

The first time you get a bill for a new engine you will see the benefits of hiring....I would turn that around by saying that if you are renting, the engine will most likely be sent to the cheapest nastiest engine shop, whereas if it is your own you will use the opportunity to get it done by the most reputable engine shop (probably in the USA), so when you fly you know there won't be too many bolts loose :)

Buying a plane with a dodgy engine is an opportunity to knock him down by the cost of an engine rebuild. It's the most important bit of the plane (along with the wing bolts).

There is little comparion between hiring and owning. If you own, you get

- total access
- ability to do fly away trips (a huge value to a pilot)
- maintenance done to YOUR standards
- know that nobody else has bent it
etc

Maoraigh1

10th Dec 2009, 19:55

I've been flying regularly since 1987. All the guys who got their licenses at that time have either gone professional, got their own plane or a share in a plane, or disappeared from regular flying. I bought a share in a Jodel in 1990. I did 100 hours last year, at an overall cost of £56 per hour. I'm still in the same group.
If I'd done 20 hours, it would have averaged at £80 per hour.
10 hours would be £110 per hour.

seymour beaver

10th Dec 2009, 19:58

An important factor is the guys you fly with as being a share holder if you get on with group members you can each do various legs and get about with shared costs doing varied trips.If you hire its possible you may just do the same old local unless you go on arranged flying club trips.

pa28r driver

11th Dec 2009, 16:22

i own .......... i love .............i skint

as per the previous replies owning has a definate bonus regarding go when where for how long and with whom u like,however you bend it .....you mend it !!!
rental,well if u break it simply give em the keys back and say sorry (with a somewhat sickly grin )
i think ive worked out the break even point for myself as flying less than 40 hours per year........rent it.
Any more than that then ownership appears to be better.
and anyway i can simply sit out at the airfield...tea in one hand ...ciggie in the other and think ......that babys mine !!!
regards to all
pete

Maoraigh1

11th Dec 2009, 21:16

"however you bend it .....you mend it !!!"
Privately owned aircraft are insured. You break it, insurance pays to mend it, just as if it was hired. You will have to pay more for your insurance afterwards - but you might find as a hirer, nobody would hire to you.
Wear and tear should be covered in your hourly + monthly charges.
At present hire charges, our group jodel becomes competitive at less than 10 hours.

Rod1

11th Dec 2009, 22:06

You are getting to different views on the scale of the risks and the brake even points. This represents the difference between C of A costs and permit costs. To replace an engine in a PA28 is likely to cost north of £15k, to replace an O200 in a permit machine can be done for a few thousand if you know the right people. As has been said, on a “Jodel type” permit machine the brake even is around 10 hours a year, on C of A, around 40 hours. There are obviously many shades of grey within each category.

Rod1

ak7274

11th Dec 2009, 22:13

85 hours in the last 12 months........Ins £900.... Hangarage £1020........Fuel......£2100.......Permit £180.....Misc parts allow £500..
Total around £4700, round up to £5000....Less than £60 an hour. Rarely fly without someone in the spare seat and not one of them (except Grandaughter) has walked away without contributing. Note to self....must tell son to pay her more pocket money. I go where and when I want, however no night and no imc.
That's my take on it for what it's worth. Whatever you do....think before you leap into buying. Think before you buy into a group (you gotta get on and the more there is, the harder it is). Think hard before buying a permit a/c. Can you do most of the work yourself?.. Have you time? Can you afford it, and the inevitable shock of it costing more than you thought?
I would rent for a while and fly a few types first, try a couple of permit types too. I am sure if you go to a fly in and introduce yourself some one will want to show his baby off.
G-BJOT Jodel D117... I love it!!!!!

IO540

12th Dec 2009, 11:54

To replace an engine in a PA28 is likely to cost north of £15k, to replace an O200 in a permit machine can be done for a few thousand if you know the right people.Unfortunately, the difference between an ownership full of aggro and an ownership which is fun is very much down to knowing the "right people" and this is as true for CofA as for a lawn mower :)

It should not be like that but GA is full of people ranging from well meaning but incompetent to outright crooks and it takes a while to put together a bunch of people one can trust....

A plane is not a BMW which you can just drop off at any BMW dealer...

A and C

13th Dec 2009, 09:09

Quote

To replace an engine in a PA28 is likely to cost north of £15k, to replace an O200 in a permit machine can be done for a few thousand if you know the right people.

The overhaul of a direct drive aircraft engine is a quite a basic engineering task but it has to be done within the limits set by the engine builder and those limits do not change just because the aircraft has an LAA permit.

So apart from saving may be £2K in labour because you can fit the engine yourself and about £500 because you don't need the Part M certification (a stab at the adminstration costs for this job by a part M company) I am at a loss to know how you save IRO £10K.

Oh! perhaps I can help.....................I know of one engine builder well liked by LAA types who builds an engine to a price. Most LAA types are very happy with this as the engine usualy runs for about 500 hours, as most of these people only do 40 hours a year the shoddy workmanship takes 11 or 12 years to become evident. This is long after any form of redress can be had for the junk the unfortunate owners have paid for.
The worst thing that I have seen from this engine builder was an engine fitted with a bent crankshaft. One of his customers got lucky and he fitted chrome rings in a chrome bore, this engine was wrecked after 50 hours with large amounts of metal in the filters. this happend so quickily that the builder in question had to refund the money, however it left the owner trying to find a set of long out of production cylinders that would be good enough to overhaul.

The fact is that you only get what you pay for and if you are happy to fly with a £4K overhaul then you had better practice your forced landing skills on a very regular basis, and seek devine help when crossing the channel.

Justiciar

13th Dec 2009, 10:46

I am a bit of a fan of the permit as compared to the C of A aircraft, really on grounds of price.

However, yesterday I flew Old Buckenham to Gamston to collect my daughter, who is at Sheffield Uni. A friend has a PA28 which he has no time to fly, so we quickly came to a reasonable arrangement. On departing Old Buck I hit some showers and low cloud. West of Kings Lynn and over the Lincolnshire fens I ran into some further low cloud, so was IMC for a while before emerging into the bright sun of a winter's day, which persisted all the way to Gamston.

Now, my daughter takes after her parent. Has her father's good looks, of course.:ok: Also has inherited her mothers inability to travel light. In fact, we have over the years held up RyanAir's share price with excess baggage. :{ Two suitcases, a laptop and a huge shoulder bag (what do they really find to carry?) all went into the rear and we headed for home.

Same cloud on the way back, this time climbing to 6000' for VFR on top all the way back to Norfolk.

What a beautiful day. The point of all this is that I could not have done this trip in my last aircraft, the Pioneer, on grounds of being both day VFR only and because of the limited MAUW. I suppose an RV of some sort would have addressed one of these issues but not the other (not legally anyway). So, sometimes you need a conventional C of A aircraft to do the business. Knowing someone who has one begging to be flown is a good solution.:}

My girl is studying photography. I didn't notice her snapping away until we got home. She has some real arty stuff, one of which will go on the wall when I have the time. I might even post here if I can work out how to do it.

Rod1

14th Dec 2009, 09:35

A&C, you are a professional engineer, I am just an amateur who built an aircraft, but;

“Oh! perhaps I can help.....................I know of one engine builder well liked by LAA types who builds an engine to a price. Most LAA types are very happy with this as the engine usualy runs for about 500 hours, as most of these people only do 40 hours a year the shoddy workmanship takes 11 or 12 years to become evident”

Interesting comment. I can only go on my “local experience”, but do many LAA people use engine shops for work on the simpler LAA types? All the ones round me do the work themselves and get it signed off by an appropriately qualified inspector, just like an aircraft build. When I had engine failure about 20 years ago a local chap helped me rebuild the engine at no cost (apart from bits) and it is still going fine as far as I know.

When the LAA got the CAA to remove the overflight restrictions it did an analysis of all the reported accidents covering the last 20 years. The analysis showed that LAA aircraft were marginally less likely to suffer a significant failure than C of A machines. This was accepted by the CAA and the restriction was removed. The report may well still be on the web site.

“The fact is that you only get what you pay for”

You are the professional and I have only been playing at this for just over 25 years, but in my experience if you want a job done well you do it yourself, you invest extra time and care and you know it is done right. Once you remove the understandable commercial time pressure, it is surprising what an amateur with some help from the LAA can do. Even thouse with little time and no experience will find the local LAA enthusiasts can be of assistance.

Rod1

IO540

14th Dec 2009, 09:52

The problem is who decides whether the amateur knows what he is doing.

Even people who do this for a living for 20 years are still often not to be trusted, and skimp on all kinds of stuff. They probably could do the job right but for some reason choose not to.

The pilot doing his own servicing has an incentive to do it right (it's called "survival" - something which the normal workshop chap doesn't need to worry about because he doesn't fly) but that doesn't mean he knows how to.

I am a pretty competent mechanical engineer, with a well equipped workshop with a lathe, a turret mill, etc, and I do the 50hr checks, and I could do a lot of the stuff which I cannot legally do under pilot maintenance rules, but I would not even dream of rebuilding an engine. It is simple mech stuff but there are all kinds of gotchas which can come and bite you later down the road.

Ultimately the pilot has the right to kill himself, in the same way as if he took up mountain climbing, but this argument falls apart if he can carry passengers.

The other factor is that most people who fly the light/sports types are doing so because they are "funding-limited" and with many there will be a great incentive to skimp on stuff. Human nature....

maxred

14th Dec 2009, 10:09

Yes, this has now developed into an interesting discussion on ,maintenance,and the cost there of. I own two aircraft, both 'vintage' and it has cost me a small fortune. However, that is my choice and decision. I am not an engineer, have little interest in the mechanics, I love to fly, and take the maintenance of my aircraft very seriously. I.E. I pay professionals to do it. I have watched in wonderment at 'tinkerers' doing their own work. They mess about, close the covers, and off, sometimes coughing and spluttering, into the blue yonder.:rolleyes: It obviously gives them some satisfaction, however, I have always been of the view that no price is too much, to ensure your surviveability at 5ooo' is given every mechanical chance. That generally comes at a heavy price. But that is life and very good luck to all the guys that take great pride in doing it themselves - and saving a small fortune on the way.:D Pockets due to be emptied again - 50 hour checks coming up.

A and C

14th Dec 2009, 10:30

I am not surprized that the LAA vs CAA aircraft accident rate is much the same because I feel that the LAA aircraft are only flown for pleasure and are not likely to venture out in bad weather.

Also due to the lower number of flying hours on LAA types they get more maintenance per flying hour than CAA types, this usualy picks up engine problems before a failure happens.

However I have seen Three LAA Lycomings overhauled and the cheap one was junk that was just about fit to tie a boat too. The other two engines were very good however the price was a lot nearer the normal overhaul price than the "£ few thousand" that you quote for an overhaul.

There is only one way to overhaul an engine.............that is the correct way using the propper tools, parts and manuals. So the only thing that the LAA can save you is the cost of the labour and I say this with my LAA inspectors hat firmly on.

S-Works

14th Dec 2009, 10:52

I think there is a bit of melodrama going on regarding rebuild standards!!

I have just done a top overhaul on our Gipsy 10-2 and carried out most of the work myself. I was quoted over £10k by a very well known Gipsy shop, my final bill came in at under £2000. This was four new pistons, four sets of rings, oil control mod and rings, re conditioning and and honing of four cylinders. I also replaced every single seal, pushrods, oil etc and lapped all the valves and replaced 3 sets of valve guides. Bead blasted and painted all of the cylinders, heads, rocker boxes etc.

I used my engineer to oversee and took the bits that needed engineering to specialist companies on a fixed price cost. All done using the Gipsy overhaul manual and all done to the exact tolerances.

I liked doing the work, I like the fact that it runs like a sewing machine and I like the fact that I know exactly how the work was done and who did it.

hatzflyer

14th Dec 2009, 11:08

Whilst I would agree with a lot of the comments on here, it always seems that this type of thread ends up the same way . "Them and us " (permit or C of A ).
This then splits up to the great "being ripped off...or I do my own permit work " debate, and very soon we'll have the " you can't fly IMC/at night brigade".
All very predicable.

But the biggest question to any potential hirer/groupie/owner , is " what do you want from your flying?"
The sad truth, is the person asking what to do (IE poster of original question ) is not in a position to know what he/she wants from their flying because they have not had experience of all the different facets of flying,only time can provide this experience.

Its very much a chicken and egg situation ,further complicated by the fact that peoples choices change as they go through life.

There are no difinutive answers.

I would like to lay one myth to rest though....people building/owning flying LAA aircraft are no longer impoverished wannabes flying marginal aircraft.
By enlarge ,they choose to fly LAA aircraft because they offer high performance that is not easy to find in production aircraft often at quite an outlay.

Rod1

14th Dec 2009, 11:13

Bose-X has given a typical example of how it works in practice. Note the costs are very similar to my generic comment!

As regards to “tinkering” I am certainly guilty of tinkering. This is the result of 1800 hours of amateur tinkering;

G-KARK (http://www.laaeastmidlands.org/GKARK.html)

Do remember though that my technical knowledge is very limited compared with A&C, I am strictly an amateur!

Rod1

Captain Smithy

14th Dec 2009, 13:15

I was also at this crossroads a while back... do I buy a share or keep renting.

The flying was much cheaper with owning a share, but the threat of maintenance bills (both planned and unplanned) put me off completely. If something got broken or a new engine was needed, on my salary there's no way I'd have been able to afford it. In the end with my financial circumstances I worked out I was better off renting.

Also I find when renting there's the variety of flying different types. I quite enjoy that freedom.

If my financial circumstances change I might consider it in the future, but not for now.

Smithy

Piper.Classique

14th Dec 2009, 14:13

If you rent you have a limited choice of aircraft and less availability. A group is better from both points of view. I share a Super Cub with my husband, so we both get plenty of flying. It's on a C of A, but we do the 50 hour inspections. It costs about the same as flying a club DR 400 but its a lot more fun and we have an appreciating asset. Yes, really. Ok, we have spent money on it but if we sold it now our flying for the last twenty years would have cost us what we paid in insurance, all the rest is covered by the increase in resale value.:ok:

seat 0A

14th Dec 2009, 14:53

For me, a big part of the fun is flying somewhere and actually getting to spend some time there. So I bought a share in a smal twin.
If you just want to spend time in the air, it is probably cheaper to rent.

IO540

14th Dec 2009, 15:10

Never forget that the total operating costs of the plane have to be recovered somehow - otherwise the owner is going to go bust / pack it in, etc.

So there will never be a free lunch.

Renting is obviously renting..... zero commitment needed on the renter's part, but there is a price to pay which is the highest hourly (marginal) cost of all the options. IOW, the cost of flying one extra hour will be highest if you are renting.

At the opposite end - owning outright or in a group - the cost of flying that extra hour will be just the fuel and any hourly maintenance items (engine fund - £10/hr on a big Lyco, 50hr check fund - say £5/hr) and not a lot else. Consequently, I can fly an extra hour in my TB20 for less than I can rent just about anything that flies faster than my lawn mower.

Now guess which of the two scenarios is going to more encourage pilot currency...

The other end result is a big difference in the incentives one has to behave like a cowboy. Look how many owners, versus renters, do you see at your local airfield starting the engine and before it warms up, driving like crazy across grass/concrete/grass so as to spend the minimum time on the ground, cutting people up in the circuit, etc.

Captain Smithy

14th Dec 2009, 16:35

Look how many owners, versus renters, do you see at your local airfield starting the engine and before it warms up, driving like crazy across grass/concrete/grass so as to spend the minimum time on the ground, cutting people up in the circuit, etc.

Quite a few people do this regardless of whether they own the aircraft or not... :uhoh:

Smithy

A and C

14th Dec 2009, 16:55

The way that I get pilots to take a little more time on the ground to taxi slowly and walm the engine is to charge from take off to landing.

This avoids the incentive to rush when on the ground

flybymike

14th Dec 2009, 22:55

I can fly an extra hour in my TB20 for less than I can rent just about anything that flies faster than my lawn mower.

First time I ever heard you call your TB20 a lawnmower...;)

IO540

15th Dec 2009, 06:45

Well, the starting procedures are quite similar, and both are well capable of prop strikes :)

The way that I get pilots to take a little more time on the ground to taxi slowly and walm the engine is to charge from take off to landing.

Agreed, and that's what I used to do when I used to rent mine out. The catch is that there is no (normal) instrument which records airborne time only, in a tamper-proof manner, so you have to trust people. Most can be trusted but not all, and those who can't will ruin the deal for the rest, by claiming silly airborne times which a subsequent EDM700 download proves to be fake.

One could rig up a running-hour meter off a squat switch or pitot pressure switch.

A and C

16th Dec 2009, 18:13

At the moment I am looking at fitting one of the loggers that the gliding people you to my aircraft to keep tabs on them.

It would seem that it would provide the type of monitoring that would let me bill people to the second! No doubt it would also tell me the ground speed and the time spent walming the engine before take off.

Returning to the subject of engine overhaul I can only think that Bose-X is a very clever bloke with a lot of kit in his shed if he can save himself that much money on a top end overhaul.

Justiciar

16th Dec 2009, 18:57

Bose-X is a very clever bloke

Well I for one am very impressed :ok: Particularly as my group is going through similar. Where is your aircraft Bose and what is it?

flybymike

16th Dec 2009, 23:21

His girlfriend is more interested in the "lot of kit in his shed..."

S-Works

17th Dec 2009, 07:19

Returning to the subject of engine overhaul I can only think that Bose-X is a very clever bloke with a lot of kit in his shed if he can save himself that much money on a top end overhaul.

It's not about having kit in my shed, it is about finding out who does have kit in there shed. You would be surprised at what rural England has in its shed. The guy that did the machining for me, charged me £40 to do the oil control mod, in his shed are lathes, stand drills, CNC and god knows what else. He renovates classic tractors as a hobby.

I picked up a set of 4 pistons for £200 from other owners of the same type.

The problem is that most people will believe their engineer when he tells them a piston is £400 each and a set of rings is £130 because it is aviation after all and we are used to being turned over. The oil control mod is a groove and set of truck oil control rings.

None of this stuff is difficult and if you have an engineer to assist who is not just interested in lining his own pockets the job can be done very cheaply.

Justiceair PM me for details.

hatzflyer

17th Dec 2009, 07:26

Its all a question of personal skills. I find top overhauling a Lycoming easier than filing a flightplan on afpex.

Horses for courses ?

IO540

17th Dec 2009, 17:18

I find top overhauling a Lycoming easier than filing a flightplan on afpex.

Hmmm; I don't think I will have you doing my overhauls :)

Assuming you know how to switch on a computer, I could teach you how to file flight plans using Afpex in under 15 mins. I don't think anyone could teach you about engine overhauls in less than years. It isn't just bolting the thing together; there is a great deal to know about tolerances, balancing, you name it. A lot of expertise goes into engine rebuilds.

Of course somebody could do a "top overhaul" (which is basically a removal of the cylinder assemblies, leaving the crankcase closed and thus leaving that can of worms firmly shut) by unbolting the cylinders, sending them off to various people to overhaul, etc, and then bolting them back on with new pistons. You need a torque wrench and not a lot else. I could do that. But I wouldn't post on a forum claiming to have done a top overhaul.

gasax

17th Dec 2009, 19:32

Well IO I suppose you are a sign of the times!

Top or even bottom end overhauls are technically not difficult. There are a clearly set out set of criteria, components and the order / method of taking them apart and putting back together - where is the problem?

Check the individual components, put them together in the right order, off you go. There is no mystery, no magic. We used to train tens of thousands of people to do this most years whilst we were a manufacturing nation.

We no longer are (well not in terms of our major industrial competitors) and suddenly simply machines become things which need highly specialised and expensive people?

There are still a large number of these people fettling away in their sheds. One of my friends is building a Group 1 replica Dolomite Sprint rally car. Straight forward you might think. But. But. The rules allow him a 2.5lt engine, so he has taken a Rover V6, turned the cylinder heads around, built inlet and exhaust manifolds, the inlets incorporating sequential electronic fuel injection. The engine is no longer transverse but longitudinal and now mates to a sequential geabox, with custom flywheel, clutch etc. Of course minor matters like sump, oil pump, fuel pump etc all need to be sorted out - after being completely re-oriented.

He rebuilt the top end of an A65, including new metal fuel lines, rebuilt carb (inc butterfly bushes), exhaust, baffles, new cylinders and after market valve gear in 3 days - working part time. His only comment - "boring little engine glad to get back to something interesting"!

My own efforts on a Gipsy and O-200 are somewahr more modest - but these are simple engines to work on, with no real 'gotchas'

Far too many 'aero engineers' are nothing of the sort, hence the mystery and expense

IO540

17th Dec 2009, 20:11

I have seen the inside of a few aero engines, including mine when the crank was being changed etc (in the USA - I flew there to "check it out" as I was writing it up for a mag) and sure there is no rocket science to it.

Yet somehow the whole UK engine rebuild business is a walking disaster. Less so in the USA than here but they do have cowboys there too. How do they manage to do crap work on a "simple" engine?

I think there is a number of reasons, mostly to do with some "less than robust" features of these engines, and probably a lot to do with idiots not using torque wrenches, or having them grossly mis-set.

There are special grinding processes on the valve guides. Easy if you know how, sure...

The crankcase skimming is pretty specialised and needs close tolerances between the mating surfaces and the crank bearing surfaces, and not many engine shops do it in-house.

There have been cases of cylinder studs being nearly stripped and they come up at some later date.

Loads and loads and loads of nuts, bolts, studs not being tightened to spec. A friend of mine got a Superior-rebuilt engine (IO-540, UK job) with IIRC 19 oil leaks. Basically, the monkeys didn't do up the crankcase bolts, etc. His mind was probably on his next sh*g, and there was no duplicate inspection.

A large % of catastrophic engine failures are probably caused by under- or over-tightened (nearly stripped) studs. Why should this happen?? Only an idiot should do something like that.

That's before you get onto dynamic balancing. You need special gear for that, to spin up the crank, measure where it is too heavy and (under appropriate FAA approvals) take a very small amount of metal off where there is no stress. Or, if you aren't approved for it, try to match an under-weight con-rod big-end to that crank bearing, and vice versa. Pistons are much easier but they need to be matched to the small ends, correspondingly.

Then there are various details like the very slight taper on the cylinder bore..

And the more specialised processes need equipment which not many firms will have kicking around and will contract it out.

Things are easier in the USA. For example the firm (http://www.bpaengines.com) which did my engine, which is the most reputable I could find (despite the naff website) is in a road packed end to end with firms doing other bits, so if e.g. the fuel servo needs doing, they take it next door. Mag overhauls, across the road. This (http://www.qualityaircraftaccessories.com/) excellent firm is down the road.

Here in the UK, if I want a fuel servo done, there are about two firms that can do it and neither of them is particularly keen... UK mag overhauls are definitely a Russian roulette, especially the single shaft ones.

None of this is rocket science but you need to be a really good engineer, and they are not being educated anymore because vocational engineering training (apprenticeships) more or less died about 30 years ago. Today's kids want spending money and they want it NOW, and no businessman will be employing "kids" on the same wages as somebody older and far more stable.