50+:1 15m sailplanes

Earlier, (Kirk Stant) wrote:

One question: how do you buy a factory-
built Sparrowhawk and register it if it
isn't certified yet?

As Experimental, Racing or Experimental, Exhibition, just like an ASW-20.

Bob K.

If you don't mind the drive to Estrella, my dad is there with his
SparrowHawk right now. Don't know how much longer he will be there
though. His is the bright orange one.

The ultralight thing is an issue for a lot of people. I don't think
anyone has ever proposed that you and yer buddies could haul it around
on a deserted road and figure out how to fly the thing. (hey y'all,
watch this!) The company has always said that the SparrowHawk should
only be flown with adequate training.

As far as getting a tow, the only thing that is usually asked for is
some kind of proof that the pilot is qualified. Without a license and
aerotow sign off, I would expect the pilot would be required to take a
tow with an instructor. Then it would be basically the same as a
student pilot on a solo flight.

Registration is exactly the same as most of the foreign glass that is
flying right now. All ASW-20's for example are factory built planes
that are not certified in the U.S.A. They are registered as
Experimental - Racing for the most part. Same as the SparrowHawks
that are registered.

I definitely am looking forward to getting to Turf. Once I get a
better idea of my plans, I will post a schedule and contact everyone
who has contacted me directly.

Happy flying,
Doug Taylor


Doug, thanks for the excellent response. I fly out of Turf Soaring,
near Phoenix Arizona - and would love the opportunity to see the
Sparrowhawk in action. I'll admit I'm a bit of a sceptic, but from
the reasoned responses from several of you out there it sounds like it
is a nice little glider.

I just wish the whole "ultralight" aspect would go away - that still
scares me. It may be a pretty moot point - I doubt anyone could show
up in an unregistered glider and get a tow at any glider operation I
know of!

One question: how do you buy a factory-built Sparrowhawk and register
it if it isn't certified yet? Or did I miss something. Just curious.

So come on out to Turf and show your stuff - on any weekend there will
be plenty of glass to keep you company on some XC or racing, and a
nice airconditioned clubhouse with cold beer and chicks waiting after
the flight (see Pez, he got it just about right, if you stay you will
have to race!).

Kirk

On 12 Jan 2004 09:41:18 -0700, (Mark James Boyd)
wrote:

Mike Borgelt wrote:

As for complexity of two jet engines compare with a horrible, heavy,
noisy vibrating two stroke with reduction drive and propeller, complex
and heavy extend /retract mechanism, heat issues if the engine is
buried in the fuselage and complex operating procedures with very
limited climb speed range. Look at the prices being charged for these
contraptions.

Compared to a two-stroke, four jet engines is an improvement.
But again, IMHO, one jet engine of the same power is better than
more engines in light wing-loaded aircraft. The complexity of
pilot management, and the extra workload to manage the feeding and
maintenance is the downside.

Even the jet Caproni was fly by wire for engine management. These
engines already come with automatic electronic controls. Not a heck of
a lot of complexity.


And redundancy is, I believe,
notional. I'd rather run out of gas and then switch to a full
tank than run out of gas on one engine and then, a few seconds
later, run out of gas on the other side.


I'm not worried about running out of gas, just Murphy's Law.

I hope we can agree as gentlemen to disagree on this one...
I'm strongly in favor of a single turbine engine for this
application.

They simply are not available yet. Two smaller turbines are and have
some advantages and I beleive aren't likely to cost significantly more
than one large one.

I've never seen a turbine airplane design that allows the hot exhaust
to reach a control surface of the aircraft. The fact that the Silent
flew a few times in this configuration is not convincing to me.
If the owner would put it on a stand in a hangar and
run it for an hour with his face right in front of the rudder/stab,
I'd change my tune. I don't have any hard facts or figures,
but my intuition sets off some warning flags here...

You can easily then cant then out a little if you want. Problem
solved(and a good argument for two engines)

I just don't know how large the heat cones are out of these engines, so
I can't really agree or disagree...I don't think I can solve this
one from an armchair...

Given you will have only an electric fuel pump you are going to want
two anyway even for one engine. You already have two fuel tanks. You
might want two batteries as well to be sure of getting a start when
about to land out. Each of two smaller engines is lighter and simpler
to swing out than one larger one.
This looks one one of those issues where the "obvious" solution isn't
so obvious on reflection. The cost of the engines seems to scale
roughly with thrust so it is dollars per Newton you pay for.
The smaller engines also have thousands of hours operating history
which is worth a lot. And I *love* the idea of engine out capability
plus with two you really aren't going to fail to get at least one
running to avoid an outlanding.

Out of gas is out of gas, period. Turbines get more reliable as they
get larger,

Maybe when you are talking about GE90 vs JT8D although I wouldn't bet
on it without doing some research. Down in the sizes we are talking
about do we have any real numbers?


and are lots more reliable than anything with a prop.
The reliability card simply has negligible meaning in this context.
And again, the cost isn't the acquisition or fuel costs, it's
continuing cost...

We aren't talking certified airplane engines here for either the
AMT450 or the AMT1500/1700. Redundancy may indeed be very nice to
have.

I figured on one tank in each wing anyway and jet fuel is much less
flammable than gasoline anyway.

The fuel is slightly less flammable but the heat danger is much
greater than a pure glider (of course). My point is just that
if one has a choice, maybe use the least flammable fuel? You
can still fill up with Jet A if needed...
And I'm also emphasizing that I think the fire risk is really
something to pay attention to and minimize by design...

I'm not sure thay make the fuel used in the SR71 anymore and it likely
wouldn't run in these engines.
The fuel and heat issues have been solved in the Jet Caproni with a
buried engine 25 years ago. There is a group in Australia converting
some non jet Caproni airframes to jet power. Same idea as Caproni but
allegedly a better and more refined installation and better
performance. I've seen it fly.

The little engines are used in R/C models. Obviously the heat issues
are solvable.

Yes and the redundancy is really nice to have. If the glider was not
capable of climbing on one I'd agree with you that one engine is
desirable but what is the point of designing around an engine that
isn't readily available with lots of operating history?
Completely true. If we MUST use two because of
marketing/availability/testing reasons
then fine. Two in the hand is better than none in the bush. But
accepting a sub-optimal design instead of making some extra phone
calls means somebody else is gonna compete with you later, at
a better price offering reduced maintenance/complexity...

Until he has a customer have an engine failure right after takeoff.

The packaging
of two is also easier.
Boy I gotta strongly disagree with that.
Installing, testing, wiring, instrumenting, fueling,
operating, shutting down, diagnosing in flight, etc.
for two engines is wholly different than one.
There's a reason 727s have three crewmembers instead of one,
and it isn't because of the complexity of the passengers
or so the Captain can take a nap...

The 727 was designed in the early 60's. Even 747s with 4 engines don't
carry FE's anymore.

We are talking something that weighs 5 pounds. Installing and mounting
it isn't that difficult. Check out the model jet websites.

I've seen and heard the R/C model jets fly. They aren't that noisy at
all. Two smaller engines over the wingroots actually shields the
people on the ground from much of the noise.

My comment about noise meaning you may get banned from the gliderport
was tongue in cheek. Here's the that should have been there...

Taxiing is still going to be problematical but then very few existing
self launchers taxi well(as opposed to Stemme's, Katanas etc and even
they would have trouble at our airport.

I've got some time in the Jet Caproni about 20 years ago and I wasn't
that impressed. When I last flew in it 10 years ago the owner had
figured it out and it was good. We are talking the same sort of thrust
weight for a 400Kg glider(most 15/18m gliders) with two AMT 450's.

Mike Borgelt

Yes, I'd very much like to see taxi capability. A short wingspan and
light weight like a Sparrowhawk is excellent for this turbine.
The extra stuff to make it taxi well would sell it to the
biggest market, "power pilots," with the best success.

You would need to check the fuel consumption at reduced power. You
might get a nasty surprise. The taxi to the strip might have fuel
consumption comparable to driving an M1A2 the same distance.

I can easily live without the taxi ability. I'm looking forward to the
Ventus Ca17.6TJ(that's TwinJet)

Mike Borgelt

Eric Greenwell wrote in message ...
yet? Or did I miss something. Just curious.

It was registered in the Experimetal class, just like your LS-6.

Curious; my LS6 is registered Experimental - Racing, but it is a
certified glider in Europe (JAR?) so I have to comply with all the
normal certified aircraft procedures. For example, I can't do annuals
on it myself.

As I understand it, the Sparrowhawk is not certified anywhere, just
registered Experimental - as in homebuilt experimental, where you can
do all the work yourself on it. I didn't know you could build and
sell aircraft that way - I thought they had to be kit built.

So it really isn't "just like my LS6", as I see it.

Or do I have all this certification stuff wrong? I havn't really read
up on it much.

Again, just curious; if the thing is safe to fly then it's all just
legal bull**** anyway...

I probably cant make it down to Estrella soon, hope it makes it to
Turf soon.

Kirk

Mike Borgelt wrote:

Yes, I'd very much like to see taxi capability. A short wingspan and
light weight like a Sparrowhawk is excellent for this turbine.
The extra stuff to make it taxi well would sell it to the
biggest market, "power pilots," with the best success.


You would need to check the fuel consumption at reduced power. You
might get a nasty surprise. The taxi to the strip might have fuel
consumption comparable to driving an M1A2 the same distance.

I can easily live without the taxi ability. I'm looking forward to the
Ventus Ca17.6TJ(that's TwinJet)

I love being able to taxi in my ASH 26 E, but the alternative is to push
a 850 lb glider to the end of the runway. If it were a turbine powered
SparrowHawk, it'd be less 200 pounds, and pushing it down to the end
wouldn't be any worse than just walking down there. Seriously, it is so
much easier to push, it's not an issue, it's just walking. I could do
without the taxi ability to avoid carrying a large of amount of fuel to
do the taxi.

About 80% of my flights have only one engine use, a climb to ~2000' agl.
The rest have another engine start, and 15% have a typical run time of
less than 10 minutes. About 3% can be as much as 20 minutes additional
run time, and the last 2% haven't exceeded 40 minutes (total of 45
minutes for the flight). I can easily avoid that 2% and be happy with 30
minutes of fuel at climb power.

What do these things use for fuel? Do we need to land at airports with
Jet A to refuel? Or a town with a hobby shop and model airplanes?
--
-----
change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

Kirk Stant wrote:

Eric Greenwell wrote in message ...

It was registered in the Experimetal class, just like your LS-6.


Curious; my LS6 is registered Experimental - Racing, but it is a
certified glider in Europe (JAR?) so I have to comply with all the
normal certified aircraft procedures.

Actually, you don't: "Experimental" gives you some leeway than
"certified" doesn't.

For example, I can't do annuals
on it myself.

Your glider doesn't get an "annual", but a "condition inspection" since
it is experimental. You and I don't get to do the condition inspections
(my glider is "experimental" also) because we didn't build the aircraft,
like one in the experimental-amatuer built category.


As I understand it, the Sparrowhawk is not certified anywhere, just
registered Experimental - as in homebuilt experimental, where you can
do all the work yourself on it. I didn't know you could build and
sell aircraft that way - I thought they had to be kit built.

So it really isn't "just like my LS6", as I see it.

The Russia AC-4 and AC-5M (for example) aren't certified, either, and
are licensed in the US in the "Experimental" category (racing and
exhibition, I assume). My ASH 26 E wasn't certified anywhere (not US,
not Germany) when I licensed it, either. A year or so later, it did
receive it's US certification, and I can convert to that category if I
wish to do so.


Or do I have all this certification stuff wrong? I havn't really read
up on it much.

It's confusing, all right.

--
-----
change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

Mike,

Let's face it: you just WANT two engines. It isn't
a matter of design or complexity or fuel or cost; you just WANT
two little turbines on your glider. It looked really cool
and it sounds neat and you want TWO. Nothing wrong with that...
:P

Mike Borgelt wrote:

Even the jet Caproni was fly by wire for engine management. These
engines already come with automatic electronic controls. Not a heck of
a lot of complexity.

They simply are not available yet. Two smaller turbines are and have
some advantages and I beleive aren't likely to cost significantly more
than one large one.

solved(and a good argument for two engines)

plus with two you really aren't going to fail to get at least one
running to avoid an outlanding.

AMT450 or the AMT1500/1700. Redundancy may indeed be very nice to
have.

The little engines are used in R/C models. Obviously the heat issues
are solvable.

Yes and the redundancy is really nice to have. If the glider was not
capable of climbing on one I'd agree with you that one engine is
desirable but what is the point of designing around an engine that
isn't readily available with lots of operating history?

Until he has a customer have an engine failure right after takeoff.

The packaging
of two is also easier.

We are talking something that weighs 5 pounds. Installing and mounting
it isn't that difficult. Check out the model jet websites.

Mike Borgelt





You would need to check the fuel consumption at reduced power. You
might get a nasty surprise. The taxi to the strip might have fuel
consumption comparable to driving an M1A2 the same distance.

Two gallons per mile? $4 to taxi to the runway? I'm fine with
that. My whole premise in this design was that 1/5 of the fuel
efficiency of a two-stroke is worth the enormous other benefits
(including 1/5 the parts count for the engine). Wasting fuel is
a feature, not a disadvantage in my mind. $10 extra a launch
in fuel is better than sending the testy ASH-26 engine
back to the factory for six months (talk to Bill Gawthrop).

Eric Greenwell wrote:

I love being able to taxi in my ASH 26 E, but the alternative is to push
a 850 lb glider to the end of the runway. If it were a turbine powered
SparrowHawk, it'd be less 200 pounds, and pushing it down to the end
wouldn't be any worse than just walking down there. Seriously, it is so
much easier to push, it's not an issue, it's just walking. I could do
without the taxi ability to avoid carrying a large of amount of fuel to
do the taxi.

An excellent point. A reflective vest and one could simply
walk the glider to the runway.

About 80% of my flights have only one engine use, a climb to ~2000' agl.
The rest have another engine start, and 15% have a typical run time of
less than 10 minutes. About 3% can be as much as 20 minutes additional
run time, and the last 2% haven't exceeded 40 minutes (total of 45
minutes for the flight). I can easily avoid that 2% and be happy with 30
minutes of fuel at climb power.

Assuming sustained flight may only require 10-20 lbs of thrust at
best L/D, fuel consumption may be quite low when used as a
turbo. On the other hand, full power may provide startling (redline)
speeds with 80-200 lbs of thrust and a 400# gross weight.

What do these things use for fuel? Do we need to land at airports with
Jet A to refuel? Or a town with a hobby shop and model airplanes?

Jet A, and some other stuff. I think they may burn just about
anything: castor oil, alchohol, melted margarine, autogas,
avgas, jet A, diesel, etc. The real problem is if the fuel
has contaminants (margarine may be a BAD idea).
Don't quote me on the fuels they use, but the turbine
principle seems to have few fuel restrictions in theory...

Eric Greenwell

Whether an aircraft is certified outside the United States makes no
difference. It doesn't even make any difference if it is certified in
the United States. Anything can be registered as Experimental -
Racing. What one has to comply with are the operating limitations
(usually stapled to the pink special airworthiness certificate or
stuffed in the pocket with it - if you don't have this, you can't fly)
and an annual condition inspection. Since anything with a special
airworthiness certificate is not really airworthy ;o), only an A&P is
required for the condition inspection, not an IA, and my understanding
is that anyone can do other maintenance as long as whatever they do
would not be considered a major alteration. None of the manufacturers
service bulletins, etc. need to be complied with technically (although
it would be a good idea). I suppose the DAR or FAA inspector could
put a paragraph in the limitations requiring that the manufacturers
recommendations must be complied with, but I haven't seen anything
like that.

(Kirk Stant) wrote in message

Curious; my LS6 is registered Experimental - Racing, but it is a
certified glider in Europe (JAR?) so I have to comply with all the
normal certified aircraft procedures. For example, I can't do annuals
on it myself.

As I understand it, the Sparrowhawk is not certified anywhere, just
registered Experimental - as in homebuilt experimental, where you can
do all the work yourself on it. I didn't know you could build and
sell aircraft that way - I thought they had to be kit built.

So it really isn't "just like my LS6", as I see it.

Or do I have all this certification stuff wrong? I havn't really read
up on it much.

Again, just curious; if the thing is safe to fly then it's all just
legal bull**** anyway...

I probably cant make it down to Estrella soon, hope it makes it to
Turf soon.

Kirk

"Mark James Boyd" wrote in message
news:4003668d$1@darkstar...

Mike,

Let's face it: you just WANT two engines. It isn't
a matter of design or complexity or fuel or cost; you just WANT
two little turbines on your glider. It looked really cool
and it sounds neat and you want TWO. Nothing wrong with that...
:P

Dude, let's face it, logging multi-engine turbine time _is_ cool!

Tim Ward