Hello fellow aviators,their own rules, but we finally got it.
Desert Aerospace is pleased to announce the first DG-808J motorglider powered by twin PBS TJ40 engines. It is a blast to fly. Here is a link to more information:
https://www.dropbox.com/s/b7m3j9tz85ga0w8/DG%20808J%20report.pdf?dl=0
The second DG is in the shop now for conversion.
Also of note...as of a few days ago, we finally won a decade-long battle with the FAA. Pilots of turbine self-launch motorgliders no longer require any special authorization. It's been a long fight and we had to play hard ball to get them to understand
On 12/5/2022 6:03 PM, Bob Carlton wrote:understand their own rules, but we finally got it.
Hello fellow aviators,
Desert Aerospace is pleased to announce the first DG-808J motorglider powered by twin PBS TJ40 engines. It is a blast to fly. Here is a link to more information:
https://www.dropbox.com/s/b7m3j9tz85ga0w8/DG%20808J%20report.pdf?dl=0
The second DG is in the shop now for conversion.
Also of note...as of a few days ago, we finally won a decade-long battle with the FAA. Pilots of turbine self-launch motorgliders no longer require any special authorization. It's been a long fight and we had to play hard ball to get them to
Congratulations! Looks nice.
Why two motors this time??
PS: My presentation wasn't so much about safety as reliability. They're
only unsafe when you trust it, and don't always fly to be safe when it fails...
Don't get too excited - Bob clearly states that this ISN'T a motorglider, but a motorized airshow glider. There is a BIG difference.
Hirth motorglider.Don't get too excited - Bob clearly states that this ISN'T a motorglider, but a motorized airshow glider. There is a BIG difference.Incorrect. The Salto with the TJ-100 is solely an airshow glider. The DG-808J does everything that the piston/propeller DG-808C does, but uses a pair of turbines to self-launch, retract and then proceed as a sailplane. Just like a Schleicher or Schempp-
Hello fellow aviators,their own rules, but we finally got it.
Desert Aerospace is pleased to announce the first DG-808J motorglider powered by twin PBS TJ40 engines. It is a blast to fly. Here is a link to more information:
https://www.dropbox.com/s/b7m3j9tz85ga0w8/DG%20808J%20report.pdf?dl=0
The second DG is in the shop now for conversion.
Also of note...as of a few days ago, we finally won a decade-long battle with the FAA. Pilots of turbine self-launch motorgliders no longer require any special authorization. It's been a long fight and we had to play hard ball to get them to understand
But why not the same single engine as used on some of the other
projects? Too big?
Why two motors this time??
The TJ40 is rated at 40 DaN (89 lbs.) of thrust. That is insufficient for self-launching.
Two engines are enough even at high altitude airfields on hot days with water ballast.
On 12/5/2022 3:03 PM, Bob Carlton wrote:understand their own rules, but we finally got it.
Hello fellow aviators,
Desert Aerospace is pleased to announce the first DG-808J motorglider powered by twin PBS TJ40 engines. It is a blast to fly. Here is a link to more information:
https://www.dropbox.com/s/b7m3j9tz85ga0w8/DG%20808J%20report.pdf?dl=0
The second DG is in the shop now for conversion.
Also of note...as of a few days ago, we finally won a decade-long battle with the FAA. Pilots of turbine self-launch motorgliders no longer require any special authorization. It's been a long fight and we had to play hard ball to get them to
Congratulations, and thank you for your perseverance. It's another stepping stone to
keeping glider requirements "real" - connected to the actual situation.
Your article was interesting and informative, but I have to offer an important correction
to a statement in it:
"What other group of aviators (or any other sport) suggests that a post-flight inspection
after every flight is critical to find things that broke? I’ve seen broken mounting bolts,
broken case bolts, stripped drive belts, and numerous other vibration/stress-induced
failures. These are way too common."
I think you were referring to piston powered self-launchers, but you didn't explicitly
state that. I think it's important to note that Schleicher Wankel powered self-launchers
do not require a post-flight inspection, and none of the owners do one, because it is a
very smooth running engine that does not cause things to unscrew, strip, crack, break, or
fall off like most of the two stroke engines used in the other gliders.
It is also worthwhile noting that, in addition to the Wankel powered gliders, that there
are hundreds of self-launchers that are also vibration free: electric powered sailplanes.
--
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation" https://sites.google.com/site/motorgliders/publications
On 12/5/2022 3:03 PM, Bob Carlton wrote:understand their own rules, but we finally got it.
Hello fellow aviators,
Desert Aerospace is pleased to announce the first DG-808J motorglider powered by twin PBS TJ40 engines. It is a blast to fly. Here is a link to more information:
https://www.dropbox.com/s/b7m3j9tz85ga0w8/DG%20808J%20report.pdf?dl=0
The second DG is in the shop now for conversion.
Also of note...as of a few days ago, we finally won a decade-long battle with the FAA. Pilots of turbine self-launch motorgliders no longer require any special authorization. It's been a long fight and we had to play hard ball to get them to
Congratulations, and thank you for your perseverance. It's another stepping stone toIt's an impressive achievement, though perhaps there is a little hyperbole in the description. In addition to the Wankel not falling apart after every flight, the statement "..but suffice to say, it will outperform any other motorglider..." does not seem
keeping glider requirements "real" - connected to the actual situation.
Your article was interesting and informative, but I have to offer an important correction
to a statement in it:
"What other group of aviators (or any other sport) suggests that a post-flight inspection
after every flight is critical to find things that broke? I’ve seen broken mounting bolts,
broken case bolts, stripped drive belts, and numerous other vibration/stress-induced
failures. These are way too common."
I think you were referring to piston powered self-launchers, but you didn't explicitly
state that. I think it's important to note that Schleicher Wankel powered self-launchers
do not require a post-flight inspection, and none of the owners do one, because it is a
very smooth running engine that does not cause things to unscrew, strip, crack, break, or
fall off like most of the two stroke engines used in the other gliders.
It is also worthwhile noting that, in addition to the Wankel powered gliders, that there
are hundreds of self-launchers that are also vibration free: electric powered sailplanes.
--
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation" https://sites.google.com/site/motorgliders/publications
hundreds of self-launchers that are also vibration free: electric powered sailplanes.
I am aware of only two types of electric self-launchers: the Pipistrel Taurus Electro and the Alisport Silent Electro. There are also the "Birdy" and the GP Jeta, but neither seems to be in actual production.
hundreds of self-launchers that are also vibration free: electric powered sailplanes.Production?
I am aware of only two types of electric self-launchers: the Pipistrel Taurus Electro and the Alisport Silent Electro. There are also the "Birdy" and the GP Jeta, but neither seems to be in actual production.
What is the cost of the conversion?
Hello fellow aviators,their own rules, but we finally got it.
Desert Aerospace is pleased to announce the first DG-808J motorglider powered by twin PBS TJ40 engines. It is a blast to fly. Here is a link to more information:
https://www.dropbox.com/s/b7m3j9tz85ga0w8/DG%20808J%20report.pdf?dl=0
The second DG is in the shop now for conversion.
Also of note...as of a few days ago, we finally won a decade-long battle with the FAA. Pilots of turbine self-launch motorgliders no longer require any special authorization. It's been a long fight and we had to play hard ball to get them to understand
I am aware of only two types of electric self-launchers:
the Pipistrel Taurus Electro and the Alisport Silent Electro.
There are also the "Birdy" and the GP Jeta, but neither seems to be in actual production.
Hello fellow aviators,their own rules, but we finally got it.
Desert Aerospace is pleased to announce the first DG-808J motorglider powered by twin PBS TJ40 engines. It is a blast to fly. Here is a link to more information:
https://www.dropbox.com/s/b7m3j9tz85ga0w8/DG%20808J%20report.pdf?dl=0
The second DG is in the shop now for conversion.
Also of note...as of a few days ago, we finally won a decade-long battle with the FAA. Pilots of turbine self-launch motorgliders no longer require any special authorization. It's been a long fight and we had to play hard ball to get them to understand
Schleicher Wankel powered self-launchersSoaring for a more extensive teardown.
do not require a post-flight inspection, and none of the owners do one, because it is a
very smooth running engine that does not cause things to unscrew, strip, crack, break, or
fall off like most of the two stroke engines used in the other gliders. Really? You might ask Keith Essex about that. This summer, I helped him remove his ASH-32 Mi engine to attempt to replace three broken case studs. We got two out, but the third was rather uncooperative. The engine had to go to Rex Mayes at Williams
The MiniLAK, Ventus 3 FES, and many other FES gliders (which includes the Silent Electro)
can self-launch. The newer mast style designs, like the AS34 and JS3RES are all
self-launchers. There are still Antares gliders flying (I think nearly 100 were produced),
and let's not forget the ones added to the fleet by people like Hank Nixon. It all adds up
to "hundreds".
--
Eric Greenwell - USA
The MiniLAK, Ventus 3 FES, and many other FES gliders (which includes the Silent Electro)On a bit of a tangent.
can self-launch. The newer mast style designs, like the AS34 and JS3RES are all
self-launchers. There are still Antares gliders flying (I think nearly 100 were produced),
and let's not forget the ones added to the fleet by people like Hank Nixon. It all adds up
to "hundreds".
--
Eric Greenwell - USA
I wonder if we should term a glider "self launch" only if it can launch ballasted at full gross weight at an airport @ 1500' (pick a reasonable altitude other than sea level) above sea level at a reasonable climb rate?
Can some of the FES systems get in the air on their own steam minus ballast? Yes of course. However, maybe we call those systems "strong sustainers"? Something to ponder.
On 12/6/2022 11:37 AM, Mark Mocho wrote:
I am aware of only two types of electric self-launchers:
the Pipistrel Taurus Electro and the Alisport Silent Electro.
There are also the "Birdy" and the GP Jeta, but neither seems to be in actual production.
There were maybe 75 electric-powered Antares built.
I flew mine ~1400 hours, but some hints on why I disposed of it: https://nadler.com/public/2020_AlmostSoaringReport/2020_DavesAlmostSoaringReport.html
And yes, this one got post-flight inspections...
On Tuesday, December 6, 2022 at 6:46:50 AM UTC-8, Eric Greenwell wrote:understand their own rules, but we finally got it.
On 12/5/2022 3:03 PM, Bob Carlton wrote:
Hello fellow aviators,
Desert Aerospace is pleased to announce the first DG-808J motorglider powered by twin PBS TJ40 engines. It is a blast to fly. Here is a link to more information:
https://www.dropbox.com/s/b7m3j9tz85ga0w8/DG%20808J%20report.pdf?dl=0
The second DG is in the shop now for conversion.
Also of note...as of a few days ago, we finally won a decade-long battle with the FAA. Pilots of turbine self-launch motorgliders no longer require any special authorization. It's been a long fight and we had to play hard ball to get them to
seem to be true, based on the stated numbers.Congratulations, and thank you for your perseverance. It's another stepping stone toIt's an impressive achievement, though perhaps there is a little hyperbole in the description. In addition to the Wankel not falling apart after every flight, the statement "..but suffice to say, it will outperform any other motorglider..." does not
keeping glider requirements "real" - connected to the actual situation.
Your article was interesting and informative, but I have to offer an important correction
to a statement in it:
"What other group of aviators (or any other sport) suggests that a post-flight inspection
after every flight is critical to find things that broke? I’ve seen broken mounting bolts,
broken case bolts, stripped drive belts, and numerous other vibration/stress-induced
failures. These are way too common."
I think you were referring to piston powered self-launchers, but you didn't explicitly
state that. I think it's important to note that Schleicher Wankel powered self-launchers
do not require a post-flight inspection, and none of the owners do one, because it is a
very smooth running engine that does not cause things to unscrew, strip, crack, break, or
fall off like most of the two stroke engines used in the other gliders.
It is also worthwhile noting that, in addition to the Wankel powered gliders, that there
are hundreds of self-launchers that are also vibration free: electric powered sailplanes.
--
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation"
https://sites.google.com/site/motorgliders/publications
The MiniLAK, Ventus 3 FES, and many other FES gliders (which includes the Silent Electro)
can self-launch. The newer mast style designs, like the AS34 and JS3RES are all
self-launchers. There are still Antares gliders flying (I think nearly 100 were produced),
and let's not forget the ones added to the fleet by people like Hank Nixon. It all adds up
to "hundreds".
--
Eric Greenwell - USA
On a bit of a tangent.
I wonder if we should term a glider "self launch" only if it can launch ballasted at full gross weight at an airport @ 1500' (pick a reasonable altitude other than sea level) above sea level at a reasonable climb rate?
Can some of the FES systems get in the air on their own steam minus ballast? Yes of course. However, maybe we call those systems "strong sustainers"? Something to ponder.
On 12/6/2022 11:42 AM, Dave Nadler wrote:
On 12/6/2022 11:37 AM, Mark Mocho wrote:Were you looking for vibration related problems?
I am aware of only two types of electric self-launchers:
the Pipistrel Taurus Electro and the Alisport Silent Electro.
There are also the "Birdy" and the GP Jeta, but neither seems to be
in actual production.
There were maybe 75 electric-powered Antares built.
I flew mine ~1400 hours, but some hints on why I disposed of it:
https://nadler.com/public/2020_AlmostSoaringReport/2020_DavesAlmostSoaringReport.html
And yes, this one got post-flight inspections...
That was what Bob mentioned, and what I addressed.
If not vibration related, what were you looking for?
Signs of hydraulic, electrical problems. Loose bits in engine bay.
Leaks, burning smell, etc.s, and....
Hirth motorglider.Don't get too excited - Bob clearly states that this ISN'T a motorglider, but a motorized airshow glider. There is a BIG difference.Incorrect. The Salto with the TJ-100 is solely an airshow glider. The DG-808J does everything that the piston/propeller DG-808C does, but uses a pair of turbines to self-launch, retract and then proceed as a sailplane. Just like a Schleicher or Schempp-
Wrong, a motorglider is PRIMARILY a glider with an auxiliary engine. This is PRIMARILY a powered aircraft that was converted from a motorglider. In other words, you would not use this machine to launch and then shut down the engine for the vastremainder of the flight.
Hello fellow aviators,their own rules, but we finally got it.
Desert Aerospace is pleased to announce the first DG-808J motorglider powered by twin PBS TJ40 engines. It is a blast to fly. Here is a link to more information:
https://www.dropbox.com/s/b7m3j9tz85ga0w8/DG%20808J%20report.pdf?dl=0
The second DG is in the shop now for conversion.
Also of note...as of a few days ago, we finally won a decade-long battle with the FAA. Pilots of turbine self-launch motorgliders no longer require any special authorization. It's been a long fight and we had to play hard ball to get them to understand
remainder of the flight.Wrong, a motorglider is PRIMARILY a glider with an auxiliary engine. This is PRIMARILY a powered aircraft that was converted from a motorglider. In other words, you would not use this machine to launch and then shut down the engine for the vast
Incorrect (again). This is intended to be used EXACTLY as a self-launch, retractable engine motorglider, with the capability of extending the turbines at any point in the flight. It does EXACTLY what your ASH-31 Mi does, but with a different powersource. Read the report again, it states this clearly. If you get past the first couple of paragraphs that describe the airshow Salto, which IS a glider that uses a turbine throughout the performance, you might notice that the engines are retractable,
Wrong, AGAIN - the description CLEARLY states that the engines can't be retracted and are fixed in place.
Holding my breath, waiting for 2G to admit he is wrong.Please don't, Mark! You will die and I am planning on having a beer with you at the brewery this summer! ;-)
Holding my breath, waiting for 2G to admit he is wrong.Please don't, Mark! You will die and I am planning on having a beer with you at the brewery this summer! ;-)
Uli
'AS'
Please do us all a favor and not compare me with 2G, AKA, DH. DH has a long history of showing symptoms of electrical shock therapy, as we say down South, "That Boy Just Ain't Right. OBTPWrong, AGAIN - the description CLEARLY states that the engines can't be retracted and are fixed in place.OK. Now you are just being stubborn, and possibly displaying OBTP symptoms.
WATCH THE VIDEO!
https://www.dropbox.com/s/a0csxezkny23roa/DG808_retract_extend_2022_07_18.mp4?dl=0
has an oil tank and recirculating oil system, it must rest horizontally in the engine bay. With a two-seat glider like the Arcus, this is not a problem, but a single seater is just a bit too small. Also, the price on the TJ100 is over twice as much as aBut why not the same single engine as used on some of the otherDefinitely too big. The TJ100 is 10.5 inches in diameter and about 22 inches long. While that would fit inside the fuselage (assuming the engine bay door opening is wide enough), there is virtually no room for the extraction mechanism. Also, since it
projects? Too big?
On Monday, December 12, 2022 at 7:01:40 AM UTC-5, Mark Mocho wrote:
Wrong, AGAIN - the description CLEARLY states that the engines can't be retracted and are fixed in place.OK. Now you are just being stubborn, and possibly displaying OBTP symptoms.
WATCH THE VIDEO!
https://www.dropbox.com/s/a0csxezkny23roa/DG808_retract_extend_2022_07_18.mp4?dl=0Please do us all a favor and not compare me with 2G, AKA, DH. DH has a long history of showing symptoms of electrical shock therapy, as we say down South, "That Boy Just Ain't Right. OBTP
On Tuesday, December 6, 2022 at 6:41:22 AM UTC-8, Mark Mocho wrote:
But why not the same single engine as used on some of the otherDefinitely too big. The TJ100 is 10.5 inches in diameter and about 22
projects? Too big?
inches long. While that would fit inside the fuselage (assuming the
engine bay door opening is wide enough), there is virtually no room for
the extraction mechanism. Also, since it has an oil tank and
recirculating oil system, it must rest horizontally in the engine bay.
With a two-seat glider like the Arcus, this is not a problem, but a
single seater is just a bit too small. Also, the price on the TJ100 is
over twice as much as a PAIR of the TJ40s.
That must be a different glider than the DG808J Bob wrote about, which includes this quote:
"Its engine is not retractable"
Both gliders were referenced in the same post, though I did wonder what,
if any, relevance the Salto had in a post about a about a modified DG 808.
Salto reference provides perspective on the prior experience Bob has
with projects of this type and I see that as useful.
Not his first rodeo.
UH
On Mon, 12 Dec 2022 23:37:41 -0800 (PST), 2G wrote:
On Tuesday, December 6, 2022 at 6:41:22 AM UTC-8, Mark Mocho wrote:
But why not the same single engine as used on some of the otherDefinitely too big. The TJ100 is 10.5 inches in diameter and about 22
projects? Too big?
inches long. While that would fit inside the fuselage (assuming the
engine bay door opening is wide enough), there is virtually no room for
the extraction mechanism. Also, since it has an oil tank and
recirculating oil system, it must rest horizontally in the engine bay.
With a two-seat glider like the Arcus, this is not a problem, but a
single seater is just a bit too small. Also, the price on the TJ100 is
over twice as much as a PAIR of the TJ40s.
That must be a different glider than the DG808J Bob wrote about, which includes this quote:
"Its engine is not retractable"
IIRC *that* comment applied to the jet Salto, not the DJ-808J: one of the videos about the 808J clearly showed its engine mount pivoting 90 degrees
and retracting.
Both gliders were referenced in the same post, though I did wonder what,
if any, relevance the Salto had in a post about a about a modified DG 808.
--
Martin | martin at
Gregorie | gregorie dot org
Hello fellow aviators,their own rules, but we finally got it.
Desert Aerospace is pleased to announce the first DG-808J motorglider powered by twin PBS TJ40 engines. It is a blast to fly. Here is a link to more information:
https://www.dropbox.com/s/b7m3j9tz85ga0w8/DG%20808J%20report.pdf?dl=0
The second DG is in the shop now for conversion.
Also of note...as of a few days ago, we finally won a decade-long battle with the FAA. Pilots of turbine self-launch motorgliders no longer require any special authorization. It's been a long fight and we had to play hard ball to get them to understand
On Monday, December 5, 2022 at 5:03:51 PM UTC-6, Bob Carlton wrote:understand their own rules, but we finally got it.
Hello fellow aviators,
Desert Aerospace is pleased to announce the first DG-808J motorglider powered by twin PBS TJ40 engines. It is a blast to fly. Here is a link to more information:
https://www.dropbox.com/s/b7m3j9tz85ga0w8/DG%20808J%20report.pdf?dl=0
The second DG is in the shop now for conversion.
Also of note...as of a few days ago, we finally won a decade-long battle with the FAA. Pilots of turbine self-launch motorgliders no longer require any special authorization. It's been a long fight and we had to play hard ball to get them to
Looks like another Desert Aerospace amazing project. I particularly like how the turbines rotate 90 degrees for extension and retraction. I believe this is the first 18-meter ship to self-launch with turbines. Congratulations Bob, I can't wait to seeit at Reno or Oshkosh.
I don't think it will see much of a market in Europe.
I don't think it will see much of a market in Europe.Correct. Noise restrictions in Europe pretty much eliminate turbines as self-launchers. Jet sustainers are OK, but ground engine runs face scrutiny.
Main issue here is WHY. Why would you want a jet self laucher? What are the advantages? Disadvantages are certainly plenty.
"How does the ground roll compare to proper self-launching DG? Published low climb rate and jet's low static thrust indicates that might be an issue."line. Liftoff is normal, but instead of climbing as slow as practical as you would with the piston/prop system, stay in ground effect until 70–85 knots is reached before beginning the climb (jets like more speed).
Try reading the DG-808J report linked in the original post:
https://www.dropbox.com/s/b7m3j9tz85ga0w8/DG%20808J%20report.pdf?dl=0
"Takeoff is accomplished by simply pushing the throttles forward to 100%. Takeoff acceleration is slightly less than with the prop, but the acceleration never slacks off. There is considerably less pitch/power coupling due to the engines' lower thrust
The initial climb will be excellent! Our tests have all been done during summer in Moriarty at a field elevation of 6200’, giving us density altitudes of 8000’ to 10,000’. Even up here, we’re seeing over 500’/minute climb at 80 knotsindicated."
Yes, the initial takeoff roll is slow (like trying to accelerate your car from a standstill in fourth gear) but as noted, it just continues to accelerate faster and faster. A propeller moves a large amount of air at a relatively low speed andacceleration starts out fast but drops off as speed increases. Jets move a smaller amount of air, but REALLY fast, and acceleration continues to increase through the takeoff.
And I don't consider 80 knots with a 500 fpm at 6,200 ft. MSL on an 8,000 ft. density altitude day to be a "low climb rate." It is definitely better than a "stock" DG-808. That's why the owner of the second DG-808 is making the switch.that two engines are twice as reliable as one, and infinitely more reliable than none.
Your statement about doubling the chance of engine failure by having two engines is an exercise in statistics. It's like saying that no engines mean no engine failures. Both statements are true, but with no failure incidents to cite, you could also say
How would the larger jet engine work in a DG-1001T?
Asking for a friend. No, really!
Dan
5J
On Tuesday, January 3, 2023 at 8:03:03 AM UTC-7, Dan Marotta wrote:
How would the larger jet engine work in a DG-1001T?
Asking for a friend. No, really!
Dan
5J
Dan, I am speaking with the DG1000T owner (I assume the same one). It will come down to the size/shape of the engine bay of the sustainer engine.
Disadvantages:
1- Cost
2- Fuel consumption
3- Noise
Try reading the DG-808J report linked in the original post:
I did, but could not find a word about ground roll.
engines.Disadvantages:
1- Cost
2- Fuel consumption
3- Noise
The oil is costly also. And JetA is not available at a surprising number of airports.. looking around recently some are 100LL only(i.e. can't assume that just because there is fuel, they would have both). Not sure if you can use diesel on these
Darren
On Tuesday, December 6, 2022 at 11:37:47 AM UTC-5, Mark Mocho wrote:
hundreds of self-launchers that are also vibration free: electric powered sailplanes.Production?
I am aware of only two types of electric self-launchers: the Pipistrel Taurus Electro and the Alisport Silent Electro. There are also the "Birdy" and the GP Jeta, but neither seems to be in actual production.
Well.....one off, "UH's" ASW-24e converted from gas to electric. I have about 100 flight hours in 2022 in it.
It has been self launched (I haven't done that yet) and I have done "saves" to altitude (testing and real) as well as self retrieve.
I have traces on Skylines if you want to see. I can tell you the flights. A real save and self retrieve were both at Newcastle this year.
As to this thread, guessing my old IPad OS and browser won't let me open the link.
Great write-up, Bob! ...And I'd love to take part in that test!jet Caproni ;o)
It will be interesting to see how the turbocharged four stroke engine compares to the normally aspirated two stroke. Unfortunately, I don't
have any numbers about power to weight ratio to compare my glider with Eric's.
I'm also interested to compare to your jet in flight, especially since
I've hyped it to a friend who's considering switching his two-stroke
engine for one of your jets.
Dan
5J
On 1/5/23 16:08, Bob Carlton wrote:
I'd like to thank Mark for stepping in with answers to questions on this forum while I've been busy. Also thanks to those who have posted valid questions and support of our efforts. Thanks to all for not turning this thread into a discussion of the
everyone, but having flown nine different PBS turbine powered aircraft over 15 years, in all conditions (hot, cold, high altitude, dry, pouring rain, aerobatics), having been the POC for all of them, and all of the SubSonex builders, I can attest toIn general, here's what it boils down to. Every aircraft is just a bunch of flying compromises. Whether piston/prop, electric, jet, tow plane, nuclear or whatever, each launch method will have its pros and cons. We realize the jet glider isn't for
pitch (constant speed) propeller, but you still only get about second gear, maybe third, given enough horsepower. A jet is a constant thrust device (actually thrust can increase with speed, but not in the speed range we fly our gliders). More like a carJets and props produce thrust differently. A propeller is a constant power device (engine horsepower). As airspeed increases, thrust decreases - a lot. It's like having a car with only first gear. This can be mitigated somewhat by using a variable
offer simpler operation, fewer moving parts, lighter weight, lower vibration, lower drag when extended, engine bay doors closed with engine extended, higher climb speed, higher climb rate, higher cruise speed, twin engines with independent systems,So...are there disadvantages to the turbine self launch glider? Sure. They are thirstier, louder, and (if retro-fitted to an existing glider) more expensive. However, from a safety standpoint (and safety is our number one priority, right?), they
really is a concern.Owners of other motorgliders can often point to one or two 'mine is better' parameters, and each single parameter will have its vocal champions, but overall, I think we've struck a pretty good balance of flying compromises, especially if safety
10 miles away (reaching a convergence line early in the morning), then time to lose 2000' with engine extended, but not running (just to be fair, I'll kill both engines in the jet since it can still climb on one). We could also include the Stemme in thisI would like to take Eric Bick up on his idea of a fly-off. We can compare the prop DG to the jet DG in the same conditions. I'd say we compare takeoff distance, time to 2000' AGL(normal thermal climb), 4000' AGL (wave climb), and time to a turnpoint
Blue skies,
Bob
Reply to kinsell: Why won't the FBO sell your friend jet fuel? Curious if they would sell him 100LL? My guess is they don't want to dispense any aviation fuel into gas cans, especially improperly labeled gas cans. I have had this problem at a couple ofFBOs years ago. I was always able to show them the aircraft, the aircraft flight manual fueling instructions, and my pump system with sealed quick disconnects and finally convince them. I now have a 26 gallon welded aluminum transfer tank permanently
I believe he showed up with jerry cans, and the FBO was not happy with
the fuel handling. This was another glider conversion to jet
self-launcher, I'm sure you know him:
https://youtu.be/U6t0BdoVRU8
On 1/6/23 4:07 PM, Bob Carlton wrote:
Reply to kinsell: Why won't the FBO sell your friend jet fuel? Curious
if they would sell him 100LL? My guess is they don't want to dispense
any aviation fuel into gas cans, especially improperly labeled gas
cans. I have had this problem at a couple of FBOs years ago. I was
always able to show them the aircraft, the aircraft flight manual
fueling instructions, and my pump system with sealed quick disconnects
and finally convince them. I now have a 26 gallon welded aluminum
transfer tank permanently installed in my truck. Somehow that doesn't
raise as many flags. Technically, at least here in the USA, and at a
publicly funded airport, I don't think they can refuse to fuel a
registered aircraft in accordance with its operation manual.
That looked like Salida, CO...
Dan
5J
On 1/6/23 22:20, kinsell wrote:
I believe he showed up with jerry cans, and the FBO was not happy with
the fuel handling. This was another glider conversion to jet
self-launcher, I'm sure you know him:
https://youtu.be/U6t0BdoVRU8
On 1/6/23 4:07 PM, Bob Carlton wrote:
Reply to kinsell: Why won't the FBO sell your friend jet fuel?
Curious if they would sell him 100LL? My guess is they don't want to
dispense any aviation fuel into gas cans, especially improperly
labeled gas cans. I have had this problem at a couple of FBOs years
ago. I was always able to show them the aircraft, the aircraft flight
manual fueling instructions, and my pump system with sealed quick
disconnects and finally convince them. I now have a 26 gallon welded
aluminum transfer tank permanently installed in my truck. Somehow
that doesn't raise as many flags. Technically, at least here in the
USA, and at a publicly funded airport, I don't think they can refuse
to fuel a registered aircraft in accordance with its operation manual.
Breakneck acceleration achieved with a downhill, downwind takeoff.
But it is clear that you want to believe that the turbine DG has "worse" performance, so I will save you the time. It probably is not as good. But by how much? We don't know.
Happy now?
On Tuesday, December 6, 2022 at 11:27:10 AM UTC-6, Charlie M. (UH & 002 owner/pilot) wrote:
On Tuesday, December 6, 2022 at 11:37:47 AM UTC-5, Mark Mocho wrote:
hundreds of self-launchers that are also vibration free: electric powered sailplanes.Production?
I am aware of only two types of electric self-launchers: the Pipistrel Taurus Electro and the Alisport Silent Electro. There are also the "Birdy" and the GP Jeta, but neither seems to be in actual production.
Well.....one off, "UH's" ASW-24e converted from gas to electric. I have about 100 flight hours in 2022 in it.
It has been self launched (I haven't done that yet) and I have done "saves" to altitude (testing and real) as well as self retrieve.
I have traces on Skylines if you want to see. I can tell you the flights. A real save and self retrieve were both at Newcastle this year.
As to this thread, guessing my old IPad OS and browser won't let me open the link.
Beautiful electric conversion on that 24! By the way Charlie, Happy New Year. I had a great time flying and conversing with you at New Castle. Hope to see you at the races this coming season!
"Why don't you motorglider guys just call them Non-Binary gliders? Old Bob, The Purist"
The DG-808J is clearly a Non-Binary glider, as it has 2 jet engines. If it was "Binary," we would have to say it has 10 engines.
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