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Cessna announces Thielert C172

We just flew EHLE-ENHF with some scenic deviations and back (approximately 3400NM) using 660 liters of Jet-A1 in 30.5 hours in a DA-40.
I guess we paid about 850,- euro in fuel costs or roughly 3 times less than we would’ve been able to do it in a LL100 aircraft like C172 and Jet-A1 was available at every single airfield we visited. It was rather funny to hear ‘PCA, please confirm you need jet fuel’ more or less every time we requested refueling.

Last Edited by kwispel at 04 Aug 21:29
EHLE

That is half the fuel price at even slightly higher speeds and a hugely increased range.

I’ve seen it said several times (including in print) that Diesel is 50% of the cost of AVGAS.

But this overlooks the doubling of miles per litre. So here in the UK the fuel cost per mile is more like a saving of 75%. This may be different in other countries with different tax regimes.
(This has to be offset against higher purchase price and maintenance costs of Diesel engines)

Assuming AVGAS at 40 litres/hour x 2000 hours TBO at £2/litre = £80k
Diesel might cost around £20k
So difference in cost of engines and extra maintenance must be less than £60k to break even and I’d suggest £20k is probably pushing it, because that would be worth more than the airframe.

(Edited because I hit return too quickly)

Last Edited by DavidC at 04 Aug 20:19
FlyerDavidUK, PPL & IR Instructor
EGBJ, United Kingdom
When there is no AVGAS at all, then this is a moot point. I was at the 6. October airport HEOC in Egypt. This is where Egypt air trains all its pilot on a fleet of C172SP. They import 100LL specifically for this and it costs $5.60 per liter (not gallon!). Jet A-1 is almost free. In other places with similar training schools, there is no AVGAS.
Look at how many C172 Cessna sells these days. Another 50 to Middle East / Asian flying schools makes a big difference.

According to GAMA report, Cessna sold 106 C172 in 2013. 5.6% or a total of 6 were sold to Middle East and Africa combined.

United States

For me it would need the same short field performance. When I had a look at the 2.0 thielert the short field performance and the useful load was better on the std. AVGAS180hp.

pmh
ekbr ekbi, Denmark

Achim,

actually I wonder. The 172 S according to Cessna cruises at 124 kts @ 75% with the O360 @ 8500 ft. 75% of 180 hp would be 135 hp at that altitude.

The 160 hp Cessna with the O320 was advertized at around 115 kts in similar conditions, so about 9 kts less with 20 hp less.

Now they claim 131 knots for the Centurion one. Ok, the Centurion 2.0s is a turbo engine, which means it can produce its full 155 hp up to about 8000 ft. That is quite a power advantage over the O360, let alone the O320.

CD 155 Datasheet

That would be a good 20 hp more than the regular “S” has, albeit at full power. Not sure how these engines are run, but for advertizing purposes… 7 kts more off a turbo charged engine giving off 20 hp more?

One wonders. I hear from people who fly the 2S that it does have quite an edge over the 1.7 and even some over the regular 2.0

In terms of pure fuel cost, the results would be quite noticeable too.

The O360 uses between 35 and 40 lph, with todays prices here that is between € 74 and €86 per hour. (Actual prices Birrfeld LSZF)
The CD55 uses between 18 and 22 lph, with todays prices here that is between €32 and €41 per hour.

With the 172S’ 53 USG quantity and one hour reserve, that means it can fly 4.3 hrs @ 120 kts = 520 NM
The Diesel with the same fuel quantity and one hour reserve will fly 9 hours @ 125 kts = 1114 NM.

If I were to buy a new Cessna today, I think I knew which one I’d go for.

That is half the fuel price at even slightly higher speeds and a hugely increased range.

Last Edited by Mooney_Driver at 30 Jul 20:04
LSZH(work) LSZF (GA base), Switzerland

Also for the Chinese market which seems to be taking off quite a bit.

And this is most likely the market they are aiming at. A friend of mine who runs a big FTO recently went to a pilot recruitment fair in China and came back blown away. China has an immense backlog in civil aviation on all levels. As they don’t have 100LL (or only in very, very limited supply), diesel is the way to go for ab-initio training there.

Achim,

not exactly new that manufacturers are bragging, is it.

Nevertheless, even with 110-120 kt (ok, they can improve on the drag a bit with todays’ techniques I hope) and this kind of fuel flow, which is more or less known for this engine, it will be interesting. Also for the Chinese market which seems to be taking off quite a bit. I hear that 10 new Mooneys were just sold there, plus 3 in the US, as well as quite some Cirruses have found their way there, so I imagine there must be a training market there where a Diesel 172 with a G1000 might be just the thing.

Here in Switzerland there are several of the original converted Thielert C172’s and they do quite well for the clubs who own them.

What I would like to see however are renewed retrofit options using that engine.

Last Edited by Mooney_Driver at 30 Jul 15:04
LSZH(work) LSZF (GA base), Switzerland

So one has to ask: what are Cessna thinking (or smoking)?

I think what they’re doing is building a limited production niche market product that can be sold to a few overseas schools.

Re cam belts – the Japanese Ministry of International Trade and Industry (MITI) actually had an investigation on the subject, because cam belt unreliability was perceived to be bringing Japan into disrepute. As a result of that and the subsequent consensus reached with Japanese auto manufacturers, their industry dropped rubber cam belts. They are still good for some engine applications, racing for instance with frequent rebuilds, and I have five vehicles equipped with them. An aircraft with a cam belt will not be joining them.

I occasionally employ a consultant who was building electric superchargers for Mazda rotaries about 20 years ago. The issue at that time was the high power required to drive the turbo.

Last Edited by Silvaire at 30 Jul 14:53

“but this is the first with a rubber cam drive belt”

Imagine the outcry when we had the first rubber / metal wheels after 2’500-odd years of wooden wheels :-)

So one has to ask: what are Cessna thinking (or smoking)?

When there is no AVGAS at all, then this is a moot point. I was at the 6. October airport HEOC in Egypt. This is where Egypt air trains all its pilot on a fleet of C172SP. They import 100LL specifically for this and it costs $5.60 per liter (not gallon!). Jet A-1 is almost free. In other places with similar training schools, there is no AVGAS.

Look at how many C172 Cessna sells these days. Another 50 to Middle East / Asian flying schools makes a big difference.

The move clearly shows where the market is heading: towards diesel engines. It will take time but it is happening.

A 135 kt C172 with a 1000 NM range will be a very attractive all round airplane

There I have to ask what they are smoking. No way it will cruise at 135 KTAS. I’ve flown the Reims Rocket which is a C172 with a 210hp engine and it is barely any faster but it climbs very well. The C172 airframe is very draggy and they are not going to change it. Also the diesel needs more cooling airflow than the Lycoming, this will further increase drag. Cruise speed at “normal” altitudes will be the same or slower, only at very high altitudes they can get an edge due to the reduced drag and the turbocharged engine but that is hardly relevant for a C172’s mission profile. It will be the same 110kt aircraft as before.

Last Edited by achimha at 30 Jul 07:17
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