Impossible Flight?

[Drzook]

Hey all,
I'm not sure if this has ever been done in real life but I don't think anyone has tried gliding across Lake Michigan. That's right, get up to a certain altitude over one beach, cut the power and land on the other side. Sounds easy enough, right?
As with all such things the Devil seems to be in the details.
I decided to use a motorglider for this for maximum realism (I know there are many gliders that could pull this off easily given the right conditions but finding a suitable towplane is another matter; besides I like the idea of having an engine just in case the gliding wasn't what I thought it would be).
I wanted to fly from Grand Haven MI to Racine WI but after looking at the ADDS NOAA aviation site I found that the higher one goes the higher the headwinds. At some point I would be flying backwards.
And so I started making calculations from Racine to Grand Haven. I tested out many motorgliders for this flight but settled on the Premaircraft HK-36 (the 80hp taildragger w/o the winglets) although Wolfgang Piper's Scheibe SF-28 seems to do much better in calm wind.
I was going to do some testing tonight and repaint it in Consolidated Blue and name it after my daughter (as I usually do when I repaint a glider of some sort) but as I was coming home tonight I noticed the blowing snow was going in the opposite direction that it normally does
...a contrary wind...I just might get a tailwind from Michigan to Wisconsin after all...
When I got home I set the weather for real and fired up the HK36 and took off from Jenison. Took a while to get to 20,000 feet and had to hit ctrl-shift-f2 to lean out the mixture above 11,000 feet (in a real HK36 I think leaning the mixture would be automatic given it's fuel injected but I don't have automixture enabled due to the multitude of other planes that need manual mixture control).
Once I got to around 20,000 feet I trimmed it out, chopped the power and feathered the prop. I kept it around 50 kts IAS and maintained a sink rate around 250-400fpm. With that tailwind getting more and more powerful as I was descending it was a snap getting to Racine. I even had around 1000 AGL to spare as I crossed over land.
I will say this however: landing a motorglider in a 19kt crosswind sucks. I was literally blown off the runway but managed to keep it intact. I only got a couple of screenies but I'm pretty happy about this flight.
Why, do you wonder, why I labeled this an 'Impossible' flight? Well, I can do this with a good stiff tailwind but I don't think it can be done otherwise. Not at least with what we use for gliders and using a decent altitude that won't cause the pilots to die of anoxia or something.

 

[srgalahad]

I'm wondering about the "how" in quite a few areas.

1. How to get to FL200... I'm surprised you could get there without a tow in any case. Thermals (in summer) wouldn't take you that high and most high-altitude soaring is done in/around mountain or 'standing' waves as are found in the lee of large mountain ranges to generate that kind of lift. A small piston engine that high.. the Rotax performance tables show that at 6.5Km the power output would be in the range of 10-15% - hardly enough to sustain a climb.

2. Wintertime... not much thermal lift on a cold, snowy winter day but certainly a lot of sink. No wonder most sailplanes are snug in their trailers while the snow flies.

3. I hope you had an oxygen installation. FAA regs (for good reason) permit flight above 10,000 ASL for no more than 30 minutes without oxygen for crew and passengers and oxygen is required for all flight above 13, 000 ASL. Then there's the thermal suit. Hopefully you had time to charge the batteries.

4. The snow.. did the weather clear out or was this IFR in cloud and possible icing conditions?

5. 19Kt crosswind... I'm surprised that, with the long wing and low gear, the certified crosswind component for the aircraft is that high. I know from first-hand experience that the tricycle-gear Katanas can be a handful at less than 15 Kts and this is the tail-dragger... Surely there were other suitable airports near Racine that had a runway which would allow landing into-wind.

Glad to see you survived...

 

[Maarten -]

My jaw fell somewhere between the rudder pedals of my Dimona. Never ever heard of such a flight in real life.

I remember having flown in a Scheibe SF-25C "Rotax" Falke as a co-pilot of a friend in July 1994. We were trying to get to a wave over the Meissner mountains (east of Cassel, Germany). At 7,500 ft the headwinds became that strong that we could fly backwards just by decreasing rpm a little bit. Never made it to the wave, but it was a great flight anyway.

Cheers,
Maarten

 

[Drzook]

I'm wondering about the "how" in quite a few areas.

1. How to get to FL200... I'm surprised you could get there without a tow in any case. Thermals (in summer) wouldn't take you that high and most high-altitude soaring is done in/around mountain or 'standing' waves as are found in the lee of large mountain ranges to generate that kind of lift. A small piston engine that high.. the Rotax performance tables show that at 6.5Km the power output would be in the range of 10-15% - hardly enough to sustain a climb.

2. Wintertime... not much thermal lift on a cold, snowy winter day but certainly a lot of sink. No wonder most sailplanes are snug in their trailers while the snow flies.

3. I hope you had an oxygen installation. FAA regs (for good reason) permit flight above 10,000 ASL for no more than 30 minutes without oxygen for crew and passengers and oxygen is required for all flight above 13, 000 ASL. Then there's the thermal suit. Hopefully you had time to charge the batteries.

4. The snow.. did the weather clear out or was this IFR in cloud and possible icing conditions?

5. 19Kt crosswind... I'm surprised that, with the long wing and low gear, the certified crosswind component for the aircraft is that high. I know from first-hand experience that the tricycle-gear Katanas can be a handful at less than 15 Kts and this is the tail-dragger... Surely there were other suitable airports near Racine that had a runway which would allow landing into-wind.

Glad to see you survived...

1. I actually did make it to FL200 on my little Rotax-powered bird but it just took a while. I had to manually lean out the engine. at that point I was going up at around 200-300fpm, significantly down from the initial 900-1100fpm at takeoff. I might have to try getting up there again with 'automixture' engaged to see if it can be done. The altitude was the main reason I didn't try this in a full blown sailplane--trying to find a suitable towplane that can get that high would be a trick and a half (for some reason visuals of a Mooney Bravo with a tow hook in the back comes to mind )
2. I don't think I would have gotten any thermal lift in summer either going over Lake Michigan and all and FS doesn't seem to model random thermals all that well. Test flights showed I could maintain 200-300fpm at 43kts IAS and that didn't seem to go down too much at 'cruising' speed (50 kts IAS and sink rate at around 300-400 fps).
3. Oh yeah. There would have been a big tank of O2 right next to me. My virtual self probably would have also gone with the same getup U-2 pilots get to wear on flights. I had all power shut off for the flight due to the way FS treats batteries--if it's just batteries on they go dead after maybe two minutes or so.
4. It was probably IFR and possible icing conditions. Things cleared out nicely just before touchdown however.
5. I don't think the Dimona/Katana Xtreme has a crosswind component of 19kts. I had the rudder deflected full right and was still drifting left on the runway. You are absolutely right--Racine did have a runway that was head on into the wind. I got nervous and didn't think I had enough altitude to pull it off--although in hindsight I probably could have done it.
Taken together this could be seen as some virtual stupidity on my part--but man it was nice seeing this come together the way it did--I was planning this flight out all week in my spare time at work.

 

[Drzook]

My jaw fell somewhere between the rudder pedals of my Dimona. Never ever heard of such a flight in real life.

I remember having flown in a Scheibe SF-25C "Rotax" Falke as a co-pilot of a friend in July 1994. We were trying to get to a wave over the Meissner mountains (east of Cassel, Germany). At 7,500 ft the headwinds became that strong that we could fly backwards just by decreasing rpm a little bit. Never made it to the wave, but it was a great flight anyway.

Cheers,
Maarten

Great story Maarten. I might have to try that; sounds like a lot of fun.:ernae:
I actually considered using Wolfgang Piper's SF25 Falke (the one with the monowheel) but it seemed underpowered for some reason (likely due to that little Limbach up front) and the sink rate seemed a bit much. I didn't try the conventional or tri-geared Falkes because I tried the SF-28 at that point and that one offers an incredible sink rate; I could definitely pull off the same flight with that but I have to get more seat time in the Tandem-Falke before trying it. I picked the HK-36 simply because I am more familiar with it; looking back I should have used the turbocharged version; would have an easier time getting to altitude.