Hey fellas,
I’ve been lurking for a several weeks now and decided to reach out for help even though I’m located in the US.
I’m interested in an early TB-20 (pre 1995) and would appreciate hearing about the experiences you owners (of TB-20s) have had with your purchase. What can I expect for maintenance costs and average performance?
Also what are your thoughts about the performance and maintenance on the turbocharged version? Have you ever thought the plane has lacked performance at altitudes?
Thanks and best regards!
Under FAA Part 91, and obviously comparing condition for condition etc, the maintenance cost should be in line with those of similar IFR tourer types.
The TB2x is a simply constructed aircraft with a very standard Lyco engine up front.
There are some metric (expensive) parts but the cost of those is not significant in the context of overall maintenance. For example there are some expensive hoses near the engine but they are replaced only at engine overhaul.
As to performance, I get 140kt IAS at low level (say 3000ft) on 11.5 USG/hr (23"/2400rpm). And a TAS of about 150-155kt on 10 USG/hr at 10000ft. It’s very economical. Range is outstanding at about 1300nm, 10000ft.
I don’t have the TB21 but turbocharged engines cost a lot more to overhaul. Also they almost never make the 2000hr TBO without cracking cylinders. The owners tend to view this as a reasonable price for the substantial extra high altitude climb rate and ceiling (25000ft versus 20000ft and a much faster climb to say 90% of the ceiling. The range of the TB21 is reported by owners I know as slightly less than the TB20, for some reason.
Every plane lacks performance! 
Peter wrote:
I don’t have the TB21 but turbocharged engines cost a lot more to overhaul.
Not true.
The cost of overhaul is exactly the same as the IO-540 used in the NA TB-20, plus the cost of the turbo, controller & wastegate overhaul.
Ask me how I know
Since no other TB21 owner has reported this, can you post the name of the company and the prices?
I know many people will be extremely interested.
Typical quotes were say 25k $ and 40k $. This was partly due to the TB21 needing a new exhaust, etc. Was yours a GT i.e. inconel exhaust?
Peter wrote:
Typical quotes were say 25k $ and 40k $.
I don’t follow you. Guessing 25k$ for NA and 40K$ for turbo ?
I have found some figures from 2008:
A full overhaul IO540 (TB20) – $32,000
A full overhaul TIO-540 (TB21) – $48,000.
These were US prices which were highly competitive by UK standards.
To some extent this reflected the relative new costs of the two engines, at around $60k and $110k respectively. The TB21 uses a very unusual variant of the TIO-540 which as far as is known was used in one other aircraft: a pilotless drone.
In addition to the above, the TB21 is likely to need a top overhaul at say 1000-1500hrs, and this is about $10-15k. I have been criticised for writing this before, and some TB21 owners on the Socata owners’ group wanted me to withdraw it, but when I asked them for evidence of a TB21 owner whose engine made 2000hrs without a top overhaul (and who owned the plane for long enough to be able to prove it) nobody managed to find one! This merely reflects the tradeoffs we have to make in the piston business, between the much better altitude performance and the higher (and to a higher degree unpredictable) engine maintenance cost.
But, referring to the original Q, this is a bit of a digression because – even in the USA – the fuel cost dominates flying costs and the engine fund is becoming less and less relevant.
Thanks for the replies!
Peter, when you mention a standard lyco up front, I recall reading in one of your blogs that this engine was actually a not so standard variant (C4D5D) of the IO-540 series.
Something about the magneto design was strange? I can’t remember exactly and didn’t really understand the technical information about it but is this true?
The engine is very common (IO540-C) but the accessory gearbox is fairly unusual (-C4D5D) and so is the use of the D3000 single shaft dual magneto.
The same magneto is however used in several others types… Cessnas, Mooneys, maybe more.
There is no issue getting the engine worked on or getting it overhauled.
pearl540 wrote:
I’ve been lurking for a several weeks now and decided to reach out for help even though I’m located in the US.
@pearl540 I recommend you read this book.
http://www.amazon.com/Flying-SOCATA-Trinidad-Tobago-Tampico/dp/1477407766/
EuroGA is an excellent place to ask what you asked but you may also have a look at this user group
