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Aux power - thrust

Lake Michigan

I've flown over Lake Michigan over a waypoint named BRAVE, once. Everything was fine and I saved time going home but my stress level increased. The next time I took that trip I flew around Chicago, over land, because I didn't want the stress. Would everything have been fine, yep, because I arrived with no problem. If I had a backup engine I would have gone over the lake. I suppose the question is, if the airplane had a backup engine (turbine) would it be used to do more? For trips over Kansas probably not needed.

V1 pulse jet test, why I don't believe they are the solution.
https://www.youtube.com/watch?v=Rdwbp6R2qM8
 
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Much better idea than a BRS chute

Steve,
I love that you are looking into this. What an interesting idea. People cram a chute with a rocket into their planes in case they get into trouble. The idea of a backup thrust source is pretty cool. How many people that try to make the infamous 180 and stall would liked to have had just a little more thrust?

I have much less fear of losing control of my plane than I do of my engine failing. Even if the little jet only burned for a few minutes, you at least get a chance to make a safer landing. It is a much better idea than a BRS chute in my opinion. I would rather do a controlled crash than have my plane floating down and landing wherever the wind took it.

On the other hand, would it push people to take more chances because they have a backup? The Cirrus safety record isn't any better than other planes - maybe their pilots are too confident and figure they can always pull the cord.
 
Steve, that was cool watching the V1 engine run -----------and do so for 4 times.

Pretty good considering that each one was designed to only make a single flight:rolleyes:
 
turn it up

Mike S said:
Steve, that was cool watching the V1 engine run -----------and do so for 4 times.

Pretty good considering that each one was designed to only make a single flight:rolleyes:
Click to expand...

Yep, I watched it four times myself. Turn it up! :)
 
FAA

The FAA advised me today that they require more discussion on their side before final decision on this matter.

A simple mockup of this turbine on the aircraft shows that it is doable.

The basic concept is a long ez style pod on a pylon under the fuselage with jettison foam bullet nose and a trailing cone to expose the turbine. The pylon will be bolted to the fuse for easy on/off.

Engine out procedure?
1. best glide speed
2. turn in direction of landing
3. open fuel valve for turbine, pull handle to jettison turbine nose and trail cone, press button for turbine start
4. primary engine trouble shooting
5. set turbine power as required
etc.

I also gave some demo flights to visiting Chinese this weekend. Turbine mockup not installed.


800px-Rutan.long-EZ.g-wily.arp.jpg
 
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Modern Marvels

Steve, on Modern Marvels today they had a segment on the glider with the retractable jet engine. It looked pretty nice and worked well. Maybe something like that just behind the canopy or like you said - in a pod just below the seats.

To go to the trouble and expense to just use it as an emergency 2nd engine may not make sense, but if there were times where the second engine was a go-no go situation over water or mountains, maybe a removable jet would be a nice thing. I am thinking of Vlad's trip up in the frozen north type of a trip.

Interesting for sure.
 
situation over water or mountains

"situation over water or mountains"

that's what I'm thinking. if the turbines can be inexpensive and the install have low drag and be quick and easy (4 bolts, 1 electrical connector, 1 fuel connection) total weight 15 lb. .... and the important stuff out of the rotor burst zone.
 
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Hybrid design

There is at least one helicopter manufacturer looking onto this for single engine helicopters. An "aux/emergency" electrical motor and battery system that would keep Nr up for say a minute after engine failure to give you time to set up for autorotation, then another 30 seconds of full power for the pull at the end.

I wonder if you had some extra room in the nose and had the shaft run from the crank, through an electric motor, to the prop, with a clutch between engine and motor, you might be able to minimize descent rate...just another way to skin this pig. Of course, the turbine idea is pretty cool, especially if it could all run on the same fuel, was designed into the airframe to be an integral part...
 
IMO this isn't about safety, it's about COOL! But a medium size pulse jet can barely push a bicycle (see that great show "Junkyard Wars"). Those model pulse jets in the earlier post only make 3 pounds of thrust. (But still - imagine lighting them up when you taxi out!) Now, what about an N-Class model rocket motor? It might provide enough thrust, before burning out, to increase your altitude significantly and thus extend your glide range and dead-stick airport options! Or act as a JATO. Imagine a Team Aerodynamix formation JATO takeoff! Or a missing man formation that lights one off!
 
Regarding electric, at first I thought about "but you have to carry around heavy batteries all the time." But the ships battery has all its stored power just sitting there to be used in an emergency. Might not last long, but might give you the short-term boost you need. You don't care if you fully discharge it in a situation like that. Would have to do the math - probably it is more like powering a toddler's Barbie Dream Car down the block and back...
 
rough drag calculation

rough calculation for the R9A with WW RV200 prop at flat pitch non rotating is 95 lb drag at 85 kt best glide speed at sea level std day conditions. turbojet thrust = 88 lb. I would not be able to maintain level flight at that speed. the flat pitch prop accounts for about 30 percent of the drag force not windmilling. a windmilling prop would have more drag. predict a drift down rate of 70 feet per minute using 88 lb of turbojet thrust. drift down from 4000 to 1000 ft AGL to traffic pattern altitude would take 42 minutes and cover 60 nautical miles. that may be good enough to make a safe landing. time to recognize the situation and turbine start time would need to be subtracted from these values.

Lake Michigan is about 75 nautical miles wide.
 
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