why aren't Motor Gliders more popular?
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why aren't Motor Gliders more popular?
i posted the above on the "Gliding" thread started by Roooooob....but no replies.
I understand there's a weight-penalty, but the absence of tow-costs for a SLMG and the "get-home" ability conferred when you run out of lift away from home-base, seem pretty compelling plusses.
Is there a lot of red-tape and restrictions that reduce their viability?
I much prefer Sailing to power-craft, but an auxiliary "donk" is a handy asset. I have always fancied gliding, but not the committed to land bit.
I understand there's a weight-penalty, but the absence of tow-costs for a SLMG and the "get-home" ability conferred when you run out of lift away from home-base, seem pretty compelling plusses.
Is there a lot of red-tape and restrictions that reduce their viability?
I much prefer Sailing to power-craft, but an auxiliary "donk" is a handy asset. I have always fancied gliding, but not the committed to land bit.
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Most common reasons:
1. Most of them are "compromise" aircraft - The high performance motorgliders (Stemme S10, ASH25Mi) make crap tourers (too big, crap baggage bay), in addition to being a bit large (Stemme is 25m with a comparatively narrow track undercarriage, which makes it a bit tricky unless you have plenty of space). Similarly a cheapo SF25/Falke/Venture has the glide performance of a K13 but under power cruises at 60kts, and after about an hour becomes bottom-numbingly uncomfortable unless you fit the seats exactly. The best "compromise" is probably a Grob 109B, of which a good one might make 30ish:1 on the glide and a 90kt cruise. Folding wings make it easier to store, but for the money there's other more sensible options. Plus they're heavy to fly.
2. Invariably they're a pain to ground handle on your own - if you don't have a hangar or leave it rigged you need at least one other person to help rig, possibly two depending on the aircraft. I can pull my Europa out of the hangar on my own and be gone in 20min. Single seaters highlight this point - unless left outdoors, which generally isn't good for the finish, still need one or two people to help rig.
There are advantages - it is undeniably cheaper to hire a motorglider than a standard SEP, and with a TMG endorsement you can use the TMG time to keep an SEP current. It's horses for courses really.
1. Most of them are "compromise" aircraft - The high performance motorgliders (Stemme S10, ASH25Mi) make crap tourers (too big, crap baggage bay), in addition to being a bit large (Stemme is 25m with a comparatively narrow track undercarriage, which makes it a bit tricky unless you have plenty of space). Similarly a cheapo SF25/Falke/Venture has the glide performance of a K13 but under power cruises at 60kts, and after about an hour becomes bottom-numbingly uncomfortable unless you fit the seats exactly. The best "compromise" is probably a Grob 109B, of which a good one might make 30ish:1 on the glide and a 90kt cruise. Folding wings make it easier to store, but for the money there's other more sensible options. Plus they're heavy to fly.
2. Invariably they're a pain to ground handle on your own - if you don't have a hangar or leave it rigged you need at least one other person to help rig, possibly two depending on the aircraft. I can pull my Europa out of the hangar on my own and be gone in 20min. Single seaters highlight this point - unless left outdoors, which generally isn't good for the finish, still need one or two people to help rig.
There are advantages - it is undeniably cheaper to hire a motorglider than a standard SEP, and with a TMG endorsement you can use the TMG time to keep an SEP current. It's horses for courses really.
They are more expensive, complicated to operate and maintain than a pure sailplane, plus some require extra licensing.
That said, they generally see better utilisation, more so the self-launchers, and the gap between the cost of a new glider and one with an engine is narrowing in percentage terms. Motors, turbos, jets, electric self-launch and sustainers are all becoming more popular.
Historically, there has been some reluctance to go down the propulsive route in the UK, partly for "purity" reasons. That seems to be going away now as people experience the advantages, especially with self-launching.
To answer the original question, they are getting more widespread, in fact all the new gliders I've seen arriving this year have had some sort of power unit. The manufacturers hardly make any without, these days...
That said, they generally see better utilisation, more so the self-launchers, and the gap between the cost of a new glider and one with an engine is narrowing in percentage terms. Motors, turbos, jets, electric self-launch and sustainers are all becoming more popular.
Historically, there has been some reluctance to go down the propulsive route in the UK, partly for "purity" reasons. That seems to be going away now as people experience the advantages, especially with self-launching.
To answer the original question, they are getting more widespread, in fact all the new gliders I've seen arriving this year have had some sort of power unit. The manufacturers hardly make any without, these days...
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A couple of friends have the jet sharks..Shark SJ + MS - HpH Sailplanes Sole UK Agency
As you can see from previous posts, there are MGs, TMGs, SLMGs and Turbos. Turbo applied to a glider is enough power to get back home, but not self launch.
One difficulty with all these motorised types is that the airframe can outlast the engine production line.
There are a number of Rotax engines in gliders that are no longer in production. I'm not picking on Rotax; it's just that I know of a few engine models they no longer produce.
The machinists can make up some bits and pieces.
Carburetors and ignition modules come from other small manufacturers who may or may not remain in business or keep the part in production.
A friend recently bought an Apis M with a Rotax 447 that is out of production. I have advised him to buy a spare engine along with the bits and pieces that might go out of production while these items remain procurable. When the time comes to sell, a spare part stock will substantially increase the resale value.
One difficulty with all these motorised types is that the airframe can outlast the engine production line.
There are a number of Rotax engines in gliders that are no longer in production. I'm not picking on Rotax; it's just that I know of a few engine models they no longer produce.
The machinists can make up some bits and pieces.
Carburetors and ignition modules come from other small manufacturers who may or may not remain in business or keep the part in production.
A friend recently bought an Apis M with a Rotax 447 that is out of production. I have advised him to buy a spare engine along with the bits and pieces that might go out of production while these items remain procurable. When the time comes to sell, a spare part stock will substantially increase the resale value.
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Glider pilot here. Another aspect I would like to add is lack of consistent engine running. Motor gliders tend to have very irregular engine running times, in my experience, making them more susceptible to failure in a critical moment. The engine is typically used only when weather is not good enough to get you home and then it is required to start up and deliver full power immediately.
Yes I know, bad flight planning and correct maintenance (run the engine) is always key...
Just my 2 cents
Yes I know, bad flight planning and correct maintenance (run the engine) is always key...
Just my 2 cents
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copy of a post I made on 9th April:
'For me it's always been motorgliders.
I love being able to soar with the engine off, enjoy being able to investigate areas where the soaring conditions look interesting (but normally are out of gliding range) and I certainly enjoy not sitting in the launch queue..............
I fly an SF-28A Tandem Falke. Not sparkling performance (28:1 with the prop fully feathered) but up there with the K13 which is perfectly adequate for the type of local soaring I like to do. Fuel burn is around 2.5 galls per hour - she'll cruise under power at 85Kts (variable pitch prop)............ and as a two seater, nice and sociable.............. On good days I range from North Norfolk down to South Essex and across to Bedford and back again.
Bad Days become average days, Average days become good days and good days become stonking days........
What not to like...........'
I do agree with some points other people are making though - particularly WRT to ageing airframes and engines - getting spares is getting harder and harder for some types. It's an area EASA fails to consider - when we run out of spares as long as there is a Type Certificate holder (not 'Orphaned') such as Scheibe for my Falke I can't do anything with regard to non-styandard repairs. The Certificate owner is not obliged to produce parts for me (they still do but at an exorbitant cost for 'one offs'). A move to permit for some types would help a lot.
Licencing is complicated - I have EASA JAA TMG, an NPPL SLMG and fairly soon an EASA Sport Pilot Licence I expect as well as an FAA PPL (Glider) - the FAA system is by far the simplest with a Glider Pilot rating on the FAA Licence and a differences check to allow the use of a Motor Glider. EASA could learn from that.........
Categories of Motorglider are way too complex - SLMG, Self Launch, TMG, Self Sustain etc........... really there should be just a rating for 'Motorglider', in the old days you could just fly a Motorglider on a CAA PPL - much simpler
But for me I don't understand why they aren't more popular - Just my 2pennyworth.........
Arc
'For me it's always been motorgliders.
I love being able to soar with the engine off, enjoy being able to investigate areas where the soaring conditions look interesting (but normally are out of gliding range) and I certainly enjoy not sitting in the launch queue..............
I fly an SF-28A Tandem Falke. Not sparkling performance (28:1 with the prop fully feathered) but up there with the K13 which is perfectly adequate for the type of local soaring I like to do. Fuel burn is around 2.5 galls per hour - she'll cruise under power at 85Kts (variable pitch prop)............ and as a two seater, nice and sociable.............. On good days I range from North Norfolk down to South Essex and across to Bedford and back again.
Bad Days become average days, Average days become good days and good days become stonking days........
What not to like...........'
I do agree with some points other people are making though - particularly WRT to ageing airframes and engines - getting spares is getting harder and harder for some types. It's an area EASA fails to consider - when we run out of spares as long as there is a Type Certificate holder (not 'Orphaned') such as Scheibe for my Falke I can't do anything with regard to non-styandard repairs. The Certificate owner is not obliged to produce parts for me (they still do but at an exorbitant cost for 'one offs'). A move to permit for some types would help a lot.
Licencing is complicated - I have EASA JAA TMG, an NPPL SLMG and fairly soon an EASA Sport Pilot Licence I expect as well as an FAA PPL (Glider) - the FAA system is by far the simplest with a Glider Pilot rating on the FAA Licence and a differences check to allow the use of a Motor Glider. EASA could learn from that.........
Categories of Motorglider are way too complex - SLMG, Self Launch, TMG, Self Sustain etc........... really there should be just a rating for 'Motorglider', in the old days you could just fly a Motorglider on a CAA PPL - much simpler
But for me I don't understand why they aren't more popular - Just my 2pennyworth.........
Arc
Originally Posted by Arclite01
Licencing is complicated - I have EASA JAA TMG, an NPPL SLMG and fairly soon an EASA Sport Pilot Licence I expect as well as an FAA PPL (Glider) - the FAA system is by far the simplest with a Glider Pilot rating on the FAA Licence and a differences check to allow the use of a Motor Glider. EASA could learn from that.........
Categories of Motorglider are way too complex - SLMG, Self Launch, TMG, Self Sustain etc........... really there should be just a rating for 'Motorglider', in the old days you could just fly a Motorglider on a CAA PPL - much simpler
Categories of Motorglider are way too complex - SLMG, Self Launch, TMG, Self Sustain etc........... really there should be just a rating for 'Motorglider', in the old days you could just fly a Motorglider on a CAA PPL - much simpler
I think that my main reasons for not flying MGs are:-
(1) Lack of opportunities to do so
(2) They don't like short runways, which is somewhat limiting.
I agree that a single motorglider rating would be better than the (apparent) current approach - and realistically it should be just differences training on SSEA or SEP: maybe a bit more training and a skill test for glider or microlight pilots.
G
(1) Lack of opportunities to do so
(2) They don't like short runways, which is somewhat limiting.
I agree that a single motorglider rating would be better than the (apparent) current approach - and realistically it should be just differences training on SSEA or SEP: maybe a bit more training and a skill test for glider or microlight pilots.
G
No, I am right.
99.99% of what the CAA used to call SLMGs in the UK & Europe are EASA aircraft & fall under EASA's rules. The CAA's nomenclature is redundant. If it has a non-retractable engine & a non-retractable propellor it is a TMG, everything else is a glider / sailplane.
You can fly your Falke on your EASA TMG, you do not need an NPPL(SLMG) & there ain't no such thing as an EASA Sport Pilot Licence so you won't need one of them.
The old / current rules are minimal training + check flight to fly TMGs on a PPL(SEP), or skills test if you actually want TMG hours to count towards SEP revalidation. New / EASA rules are minimal training + skills test to add TMG to LAPL(A), PPL(A), LAPL(S) or SPL. I don't see what is so complicated.
99.99% of what the CAA used to call SLMGs in the UK & Europe are EASA aircraft & fall under EASA's rules. The CAA's nomenclature is redundant. If it has a non-retractable engine & a non-retractable propellor it is a TMG, everything else is a glider / sailplane.
You can fly your Falke on your EASA TMG, you do not need an NPPL(SLMG) & there ain't no such thing as an EASA Sport Pilot Licence so you won't need one of them.
Originally Posted by Genghis the Engineer
I agree that a single motorglider rating would be better than the (apparent) current approach - and realistically it should be just differences training on SSEA or SEP: maybe a bit more training and a skill test for glider or microlight pilots.
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Well, what a response! thanks, all.
some of the "new" prices .....NO! all of them, are in "lottery-winner" territory, as far as I'm concerned.
The spares situation with older aircraft, is something I really hadn't thought about....I read of "difficulties" but even the most arcane stuff seems to be procurable ( thinking of the wonderful Pobjoy-powered self-build nearing completion) I think that the relatively small quantity of motor-gliders, coupled with the fragmented power-unit market, will, indeed, present challenges in the future......Type -certificate-holders using it as a "ransom-note" is a problem the authorities should address ( Though many people are under a false impression of how much is involved in "one-off" production.
As an aside, a model-engineer scratch-built 6 traction engines....he reckoned it took less than twice the time of making a single one.
Ghengis , as usual, makes an astute observation.....RUNWAY-LENGTH
pretty obvious, I suppose, low-drag airframe and high L/D ratio would infer a long landing-distance (how do airbrakes/spoilers affect this? )
I'd assume takeoff is somewhat protracted on grass, due to low engine-power and ground-drag.
Arclite really had me thinking " that is affordable, fun flying.
*breaks open mattress and starts counting*
some of the "new" prices .....NO! all of them, are in "lottery-winner" territory, as far as I'm concerned.
The spares situation with older aircraft, is something I really hadn't thought about....I read of "difficulties" but even the most arcane stuff seems to be procurable ( thinking of the wonderful Pobjoy-powered self-build nearing completion) I think that the relatively small quantity of motor-gliders, coupled with the fragmented power-unit market, will, indeed, present challenges in the future......Type -certificate-holders using it as a "ransom-note" is a problem the authorities should address ( Though many people are under a false impression of how much is involved in "one-off" production.
As an aside, a model-engineer scratch-built 6 traction engines....he reckoned it took less than twice the time of making a single one.
Ghengis , as usual, makes an astute observation.....RUNWAY-LENGTH
pretty obvious, I suppose, low-drag airframe and high L/D ratio would infer a long landing-distance (how do airbrakes/spoilers affect this? )
I'd assume takeoff is somewhat protracted on grass, due to low engine-power and ground-drag.
Arclite really had me thinking " that is affordable, fun flying.
*breaks open mattress and starts counting*
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Interesting comment x933 makes that a Stemme S10 is a "crap tourer".
I know of someone who flew one from the UK to New Zealand.
They've got about 10 hour endurance.
Doesn't seem "crap" to me!
I know of someone who flew one from the UK to New Zealand.
They've got about 10 hour endurance.
Doesn't seem "crap" to me!
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That is until you turn up at the average GA airfield - and find you cannot get between the markers, cannot turn around, simply do not fit!
We have a Taifun at my field, needs three people to unfold it - I refer to it as a Perodactyl. One person cannot actually move it when in the hangar. Virtually needs a gale or the curvature of the earth to get airborne. Lovely when flying and murderous on maintenance and care when not.
We also have a Grob - which is much more practical - buit still needs a fair amount of space and has an engine which seems quite frail. Endurance is certainly not everything.
We have a Taifun at my field, needs three people to unfold it - I refer to it as a Perodactyl. One person cannot actually move it when in the hangar. Virtually needs a gale or the curvature of the earth to get airborne. Lovely when flying and murderous on maintenance and care when not.
We also have a Grob - which is much more practical - buit still needs a fair amount of space and has an engine which seems quite frail. Endurance is certainly not everything.
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All aircraft are a compromise but to say an S10 is a crap tourer because it's got big wings and small baggage load is just picking on two of its aspects.
I own a Grob 109 and I regularly tour in it to the continent. Southern France, over the Pyrenees into Spain, South Germany etc etc. Recently spent 2 weeks in the French Alps. It is heavy and does have limitations getting out of short fields but it makes a fantastic tourer. Less than 15 litres and hour at 85-90 knots, comfortable, fantastic visibility, very stable and very cheap to operate compared to a standard SEP. And I know which I'd rather be in if the engine quit.
I own a Grob 109 and I regularly tour in it to the continent. Southern France, over the Pyrenees into Spain, South Germany etc etc. Recently spent 2 weeks in the French Alps. It is heavy and does have limitations getting out of short fields but it makes a fantastic tourer. Less than 15 litres and hour at 85-90 knots, comfortable, fantastic visibility, very stable and very cheap to operate compared to a standard SEP. And I know which I'd rather be in if the engine quit.
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A 25m wingspan and narrow track undercarriage mean you have to pick your landing airfields a little bit more carefully. Crap is a little harsh I agree, but if I wanted a motor glider for touring i'd be looking for a Dimona or G109B.
That said, There was an article in S&G many eons ago about a pair of DG400's that went touring into Europe from the UK. Anything is possible with a little creative packing...
That said, There was an article in S&G many eons ago about a pair of DG400's that went touring into Europe from the UK. Anything is possible with a little creative packing...