Sustainers and Self-Launchers- How often and for how long do you runyour motors (after launch)?

On Sunday, April 20, 2014 12:31:16 AM UTC-4, Eric Greenwell wrote:

If a pilot isn't using the FES on 10% to 20% of the flights, the pilot
has wasted his money buying the FES. The FES can and should be used to
increase the amount and quality of soaring the pilot does, and flying so
conservatively it's rarely needed will not achieve that goal.

Does this hold true in practice for most pilots and most propulsion systems?

What's your theory/philosophy on motor use and to what extent does your logbook conform to your goal?

Do FES flyers use their motors more frequently than petrol-powered pilots?

Does a motor increase the number of 'good soaring days' for you?

On Sunday, April 20, 2014 7:34:21 AM UTC-7, son_of_flubber wrote:
On Sunday, April 20, 2014 12:31:16 AM UTC-4, Eric Greenwell wrote:



If a pilot isn't using the FES on 10% to 20% of the flights, the pilot

has wasted his money buying the FES. The FES can and should be used to

increase the amount and quality of soaring the pilot does, and flying so

conservatively it's rarely needed will not achieve that goal.



Does this hold true in practice for most pilots and most propulsion systems?



What's your theory/philosophy on motor use and to what extent does your logbook conform to your goal?



Do FES flyers use their motors more frequently than petrol-powered pilots?



Does a motor increase the number of 'good soaring days' for you?

I run the (gas) motor before every flight, because I self launch every flight.

It does increase the number of 'good' days a little because I will go cross country on a more marginal day than I might have otherwise. Not because I will fly low over unlandable terrain, but because the inconvenience of a retrieve from an airport is mitigated. The 10-20% number Eric refers to seems high to me. I have started the engine for a real retrieve I think six times in 14 years. I have restarted it maybe 4 or 5 times for a relight shortly after shutdown.

Flub: You should get out and fly some more and not worry so much about what
other folks do with their equipment.

As to use of the engine - I was once on the far side of Pike's Peak from
Black Forest in a borrowed ASW-24E that I self-launched and was getting low.
No problem; I simply extracted and started the engine. As I established a
stable climb the engine quit due to fuel starvation (out of gas) so I stowed
it and landed at Canon City. The owner brought the trailer and I bought
dinner. A wonderful day!

"jfitch" wrote in message
...
On Sunday, April 20, 2014 7:34:21 AM UTC-7, son_of_flubber wrote:
On Sunday, April 20, 2014 12:31:16 AM UTC-4, Eric Greenwell wrote:



If a pilot isn't using the FES on 10% to 20% of the flights, the pilot

has wasted his money buying the FES. The FES can and should be used to

increase the amount and quality of soaring the pilot does, and flying so

conservatively it's rarely needed will not achieve that goal.



Does this hold true in practice for most pilots and most propulsion
systems?



What's your theory/philosophy on motor use and to what extent does your
logbook conform to your goal?



Do FES flyers use their motors more frequently than petrol-powered pilots?



Does a motor increase the number of 'good soaring days' for you?

I run the (gas) motor before every flight, because I self launch every
flight.

It does increase the number of 'good' days a little because I will go cross
country on a more marginal day than I might have otherwise. Not because I
will fly low over unlandable terrain, but because the inconvenience of a
retrieve from an airport is mitigated. The 10-20% number Eric refers to
seems high to me. I have started the engine for a real retrieve I think six
times in 14 years. I have restarted it maybe 4 or 5 times for a relight
shortly after shutdown.

son_of_flubber wrote, On 4/20/2014 7:34 AM:
On Sunday, April 20, 2014 12:31:16 AM UTC-4, Eric Greenwell wrote:

If a pilot isn't using the FES on 10% to 20% of the flights, the pilot
has wasted his money buying the FES. The FES can and should be used to
increase the amount and quality of soaring the pilot does, and flying so
conservatively it's rarely needed will not achieve that goal.

Does this hold true in practice for most pilots and most propulsion systems?

== I have no idea about "most" pilots, but I know self-launching pilots
that do an in-flight restart only every two or three years; I typically
use the engine for self-retrieving or saving a flight 15% to 20% a year,
quite consistently over the 19 years I've owned my ASH 26 E.

What's your theory/philosophy on motor use and to what extent does your logbook conform to your goal?

== Because I don't have to worry about a retrieve, I often linger in
distant (but good) soaring conditions rather than running for home when
the soaring starts to die there; sometimes I'll launch (too) early and
use the motor a time or two until things firm up; or check out some odd
but interesting weather situation that may not have enough lift. My
"Guide" (see the link below) goes into more detail.

Do FES flyers use their motors more frequently than petrol-powered pilots?

== I'd expect so, given the ease and reliability of the FES, but I don't
think there are enough of the FES to conclude anything.

Does a motor increase the number of 'good soaring days' for you?

== Absolutely! With a self-launcher, I can fly when and where I want,
and I've flown areas in Florida, in Alaska, and most places in between.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorg...ad-the-guide-1
- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm
http://tinyurl.com/yb3xywl

As well as my response in the Ventus FES thread, I might add that in other flights in 2011 and 2012 I used the FES to do cross country flights that I would otherwise not have attempted but instead stayed local - just because the risk of outlanding would have been too high with small, weak thermals and probably dead areas or periods. I did stay within "motor home" distance of the airfield, say 30 miles to be on the safe side, but it is all practice.

During another flight on a barely soarable day, in hilly country I was visiting rather than my usual flat home area, I used the FES to explore local hills to see if any gave useful ridge lift (they didn't - not enough wind - but it all experience, and enjoyment).

Chris N

I have been flying a self-launcher for 7 seasons - I am based in the flattish South-East of the UK. Previously I flew a pure glider, and used to land 'out' at other airfields maybe four or five times a year, and to land in a field on average over several years once a year.

Now I start over landable terrain a comparable number of times, which is maybe about 15% of my cross country flights. In two different self-launchers I have always started over somewhere which I thought to be safely landable (although I have not been tested) and I have been lucky enough that the engine has always started first time and I have been able to climb away with the loss of only about 100 foot from starting to raise the prop (which I do at 1,000 foot on downwind).

Benefits for me a

I am not an early riser; I can get to the airfield when I want, and not have to worry about being at the back of the launch queue.

I can launch to a part of the sky which I choose - I am more relaxed about whether it is soarable when I launch, and more ready to take a high launch because of not having to pay for the aerotow.

I can fly cross country on a day when I absolutely need to be home in the evening. I continue with my planned task when without an engine I might have turned home early, if I think there is the slightest chance of success.

I have no doubt that I do more soaring as a result of having an engine. For me the independence from the launch queue is such a significant part of what I was looking for that I would not consider an FES or jet sustainer. An electric self-launcher is interesting, but at the moment the endurance is very limiting. (I have an Arcus M - available as an electric self launcher but for more money with a total climb potential of 2,000 m. I was interested to read here about the EB29 electric self-launcher - does anyone know what endurance that has?).

Mark Burton, London Gliding Club, UK


On Sunday, 20 April 2014 15:34:21 UTC+1, son_of_flubber wrote:
On Sunday, April 20, 2014 12:31:16 AM UTC-4, Eric Greenwell wrote:



If a pilot isn't using the FES on 10% to 20% of the flights, the pilot

has wasted his money buying the FES. The FES can and should be used to

increase the amount and quality of soaring the pilot does, and flying so

conservatively it's rarely needed will not achieve that goal.



Does this hold true in practice for most pilots and most propulsion systems?



What's your theory/philosophy on motor use and to what extent does your logbook conform to your goal?



Do FES flyers use their motors more frequently than petrol-powered pilots?



Does a motor increase the number of 'good soaring days' for you?