Really the cheapest way to fly...

Capt.Doug wrote:
"Bret Ludwig" wrote in message There are two basic "families" of PT6
engines ....
Most twins are not really safe to to do
that with considering the dismal single engine performance and lack of
single lever power control (which coupled with their 1950s panels means
they desperately need a F/O or F/E in the right seat).

Apples to oranges- most twins equipped with PT-6s have decent single-engine
performance, and decent safety records.

I agree. The recips are the problem. The turbines have effectively
single lever power control, and surplus power at low altitude.
However, the insurers will insure Dennis the Doctor in a 414 but not a
King Air....ass-backwards.

Turbines are simpler to fly, and probably are cheaper to build per
horsepower than the LyCon engines. CNC machining and lowered high
energy metals prices reduced the production costs considerably, but the
prices didn't come down. They have in fact gone up at a higher rate
than inflation-the PT-6 has been in production since JFK was president.
The TBO has gone up and power and BSFC have come down, true. But the
profit margins are phenomenal now, and certainly weren't lean then-and
when it was designed it specifically was announced that it was made as
simple as possible so as to compete with the growing flat engines and
the radials which were still available new. I have heard numbers
between $12 and $20 thousand as production costs on these today. P&WC
is very coy with pricing but I don't think Joe Average can get a new in
crate PT6 for less than $500K today. (ST6s are available for less but
you can't get a prop drive on the front.)


The former Allison 250 series of engines is also a fair powerplant
especially in the Soloy remote redrive configuration with less fuel
burn, less weight, but is not so elegant or simple.

The C-250 series never caught on for fixed wing applications. There must be
a reason (says the former NOMAD N-22 driver).

Too expensive. The turbine Maule is $400K, the recip $100K.


The Garrett 331 is
a piece of ****, but if cheap enough I'd rather fly behind one of those
than a Lycoming, and its noise would rally the troops on the front of a
mini-warbird or aerobatic biplane, wouldn't it?

Fighting words to me. I have 5000 hours behind -331s. They are dependable
and have lower BSFCs compared to PT-6s.


The 331 Garrett takes a colossal amount of power to start (and has
only electric, not air impingement or cartridge start), is extremely
loud, and is not significantly cheaper than the PT-6. The PT-6 is
almost perfect, except it has grown in power and price like Topsy. I
had hoped the ex-WarPac nations would undercut P&WC and force their
margins (which are phenomenal!) down, but they aren't too smart at
business.

Single shaft turbines just don't make engineering sense for smaller
applications. I don't think Garrett has ever found much non-aviation
use for the 331 whereas the ST6 (the aeroderivative PT6 non-propulsion
engine) has been a phenomenal seller, relatively speaking.

"Bret Ludwig" wrote in message
However, the insurers will insure Dennis the Doctor in a 414 but not a
King Air....ass-backwards.

Looking at indemnity tables from the insurers' point of view, it makes
sense. The doctor can be insured for the King-Air as easily as for the
C-414. It just costs more because the hull liability and passenger indemnity
claims are greater.

I have heard numbers
between $12 and $20 thousand as production costs on these today.

Compare the cost of a new PT-6 to that of a new Walter 601. Perhaps we
agree on this point. Perhaps Walter isn't afraid of product liability law
suits. Walter also doesn't have a world-wide service organization available
24/7 like you get when you pay the extra money.

Too expensive. The turbine Maule is $400K, the recip $100K.

Or because they can't handle high power output for extended periods of time
as required for fixed wing use. The bearings crap out.

The 331 Garrett takes a colossal amount of power to start (and has
only electric, not air impingement or cartridge start), is extremely
loud, and is not significantly cheaper than the PT-6.

A properly maintained battery will provide all the starting amperage
required. Most PT-6s are not equipped for air impingment and/or cartridges
either, so where is your valid point? The noise from a Garret is loud for
the lineguy, but the cabin is no louder than a comparable airplane with
PT-6s. What counts is the fly-over noise which is virtuaally the same for
both engines. As for cost, why should it be any cheaper?

Single shaft turbines just don't make engineering sense for smaller
applications. I don't think Garrett has ever found much non-aviation
use for the 331 whereas the ST6 (the aeroderivative PT6 non-propulsion
engine) has been a phenomenal seller, relatively speaking.

If one wants an airplane engine, who cares about derivitives? Single-shaft
turbines burn less fuel than comparable free-turbine engines. THAT makes
engineering sense. You are really reaching to sustain your argument.

Now how about addressing that little PT-6 problem with the rear turbine
bearing. The problem continued into the late 1990s. It took Pratt a long
time to address the fix and issue an AD. All engines fail, including your
beloved PT-6. They may last longer than piston engines, but they still fail
on occassion. The Garrets are every bit as good and burn less fuel.

Just wondering-
How much PT-6 and Garrett experience do you have as mechanic or pilot? Did
you arrive at your conclusions by listening to pilots and mechanics?

D.

Capt.Doug wrote:
"Bret Ludwig" wrote in message
However, the insurers will insure Dennis the Doctor in a 414 but not a
King Air....ass-backwards.

Looking at indemnity tables from the insurers' point of view, it makes
sense. The doctor can be insured for the King-Air as easily as for the
C-414. It just costs more because the hull liability and passenger indemnity
claims are greater.



I have heard numbers
between $12 and $20 thousand as production costs on these today.

Compare the cost of a new PT-6 to that of a new Walter 601. Perhaps we
agree on this point. Perhaps Walter isn't afraid of product liability law
suits. Walter also doesn't have a world-wide service organization available
24/7 like you get when you pay the extra money.

Product liability is largely, not wholly, a crock of ****. If product
liability insurance were outlawed P&W would not be much impacted, they
have had few suits and have never had a really big one that I know of.
Cessna, Piper and Beech bred the problem by settling out of court
making them an exceedingly attractive nuisance, so to speak. Outlaw
confidential out of court settlements or outlaw or preload up (put a
big sales or excise tax on PL insurance premiums) PL insurance and
you'd be surprised how it will go away. Lawyers don't really want to go
to trial, and they really, really don't want to win only to be handed
the keys to the plant. It's their secret nightmare.

That said, FedEx makes the Czech Republic two days away partswise,
max, most anywhere in the world. And even P&W isn't getting a fuel
controller or T-wheel to you overnight in Antartica.


Too expensive. The turbine Maule is $400K, the recip $100K.

Or because they can't handle high power output for extended periods of time
as required for fixed wing use. The bearings crap out.

????


The 331 Garrett takes a colossal amount of power to start (and has
only electric, not air impingement or cartridge start), is extremely
loud, and is not significantly cheaper than the PT-6.

A properly maintained battery will provide all the starting amperage
required. Most PT-6s are not equipped for air impingment and/or cartridges
either, so where is your valid point? The noise from a Garret is loud for
the lineguy, but the cabin is no louder than a comparable airplane with
PT-6s. What counts is the fly-over noise which is virtuaally the same for
both engines. As for cost, why should it be any cheaper?

It should be cheaper because it's just not as well designed, to put it
country simple. A two shaft engine is easier to start, easier to
maintain, and simpler to control.

Single shaft turbines just don't make engineering sense for smaller
applications. I don't think Garrett has ever found much non-aviation
use for the 331 whereas the ST6 (the aeroderivative PT6 non-propulsion
engine) has been a phenomenal seller, relatively speaking.

If one wants an airplane engine, who cares about derivitives? Single-shaft
turbines burn less fuel than comparable free-turbine engines. THAT makes
engineering sense. You are really reaching to sustain your argument.

The aircraft market is small enough the economics virtually dictate
multiple use technologies wherever possible. A standard aircraft oil
pressure gauge for recips is $300 new, a Stewart Warner one for
"everything else" is $20. Is the aircraft one in any shape or form more
reliable? No.

Now how about addressing that little PT-6 problem with the rear turbine
bearing. The problem continued into the late 1990s. It took Pratt a long
time to address the fix and issue an AD. All engines fail, including your
beloved PT-6. They may last longer than piston engines, but they still fail
on occassion. The Garrets are every bit as good and burn less fuel.

Yes, they do. That's another discussion.

Just wondering-
How much PT-6 and Garrett experience do you have as mechanic or pilot? Did
you arrive at your conclusions by listening to pilots and mechanics?


My ST6 experience is on gensets in ground standby and peak shaving
apps. I also was involved with a couple of marine installations, one a
converted L-1011 ST6 APU into a river tug and the other a PT6 in a
Cigarette boat. I am not an A&P although I am eligible via the
experience requirements (Cessna Wallace and Pawnee, Bombardier) . Since
I don't actively fly right now (and won't be flying until I go another
round of surgery) and have no incentive I'm not going to take the O&P
to win points on a newsgroup.

"Bret Ludwig" wrote in message ????
My ST6 experience is on gensets in ground standby and peak shaving
apps. I also was involved with a couple of marine installations, one a
converted L-1011 ST6 APU into a river tug and the other a PT6 in a
Cigarette boat. I am not an A&P although I am eligible via the
experience requirements (Cessna Wallace and Pawnee, Bombardier) . Since
I don't actively fly right now (and won't be flying until I go another
round of surgery) and have no incentive I'm not going to take the O&P
to win points on a newsgroup.

Am I correct that you have little experience with Garretts in fixed-wing
applications?

D.