Generated electric?

[airguy]

Originally Posted by Mike S

Except that it should be a RV-36.

Makes no difference. By that point we'll have radar-guided autoland systems that make every landing a perfect 3-point.

[gmcjetpilot]

Originally Posted by RV8RIVETER

For a future engine, my thoughts are turning to gas/jet generator to power electric motor, ie series hybrid if you want to use the auto term. Anybody else have any thoughts ?

A self launched or winch launched glider? Its wind and solar powered!

Electric? Not even soon for cars. Right now electric cars are novelties and not on par with the fill'er up drive cross country of gas cars. May be 20 years for cars, but planes the weight/volume issues are greater. Hydrogen fuel cells are promising but cost, safety and infrastructure is an issue. Of course manufacturing hydrogen takes energy, electrical energy. The no free lunch rule.

In the past 100 years we used a 1/3rd of all oil, the oil that is easiest to get.

The next 3rd will be harder to get and of couse will not last 100 years at current use rates.

The last oil or related fossil energy, oil from coal, shale oil or lighter hydrocarbons (gaseous) are just more difficult to get, process and use, aka expensive, lower volume and of course higher cost.

The "other" oil, like natural gas, a gaseous fossil fuel (methane, propane, natural gas) has been used for power generation, heat and moving vehicles. Even Piper considered and tried propane plane long ago, but there are technical difficulties. The good news is there is LOTS of natural gas under the ground, even more than oil some say.

When will the proverbial shizzle hit the fan? Probably 40 years, depending on many factors, may be 60 yrs, may be less than 40 yrs. In about 60-100 yrs (when I won't care) thing will be desperate fuel wise, if technology does not have suitable substitutes for fossil fuel. Home and cars I see many alternatives: Nuke, Solar, Wind, (hydrogen) fuel cells and who knows.

Planes? That is a different story, high energy density. Currently electric is not going to happen practically or large scale for plane due to battery technology. Can you imagine an electrical engine making 20,000 to 90,000 lbs of thrust a typical commercial jet engine produces. Even making 100 hp for extended periods is not likely to be practical anytime soon, may be ever?

100LL (really 95UL is the future) will be avaiable through out our life and our kids (may be), its just a matter of cost. Don't panic. A RV flown prudently can get into the 30 mpg, easily 25 mpg. Not super when compared to a super econ-O-box car but not far off. An sub compact car of course does not do the better part of 200 mph.

Bottom line our hobby just got way more expensive. Gas will be avaiable, just a matter of if you can afford it. Really we'll be looking back on the $100/barrel days as the GOOD OL DAYS. Actually its already at $120/barrel. So the good ol days was just last month.

[Roddzilla]

Electric motor driven by a solar t62 and light weight alternator unit. Should be easy to get 100KW out of such a unit.

Actually, this is perhaps a better use of the solar t62 (or whatever model they are using) turbine than what Innodyne is trying.

I pray they can deliver a 300 HP turbine that sips diesel... but know better.

This could be done, but right now might be too heavy to get off the ground. Heck, if your running a turbine to generate electricity might as well ditch the electric motor and use the turbine to drive the prop -- Same fuel burn.

Nevermind. Reality has set in and I need to get back to writing my investment check to Innodyne

DR

[gmcjetpilot]

Originally Posted by Roddzilla

Electric motor driven by a solar t62 and light weight alternator unit. Should be easy to get 100KW out of such a unit.

Actually, this is perhaps a better use of the solar t62 (or whatever model they are using) turbine than what Innodyne is trying.

I pray they can deliver a 300 HP turbine that sips diesel... but know better.

This could be done, but right now might be too heavy to get off the ground. Heck, if your running a turbine to generate electricity might as well ditch the electric motor and use the turbine to drive the prop -- Same fuel burn.

Nevermind. Reality has set in and I need to get back to writing my investment check to Innodyne

DR

Turbines do sip diesel and actually kerosene or even gas. The problem is turbines are NOT fuel efficient. Powerful, light, compact, reliable and capable of making huge power, but the specific fuel consumption per HP is much higher than a piston engine in the 300HP range or any range. Of course piston engines above a certain size say more than 600-2000 hp is not practical with a piston engine, and turbines rule in the weight to power ratio. Still fuel economy is not a selling point of turbines.

I think you ran around the logic circle on your own. A turbine for a small GA plane is not likely to ever meet the SFC of a piston engine. If we could only improve thermal dynamic efficiency. As you know gasoline engines are only 37% efficient (even with turbos), meaning they throw away 63% in heat. So if you could double efficiency that would be great. If any of you figure out how please call me or write me, I have some money to invest.

PS: As far as Innodyne its not a turbine its a toy, a single stage that is not even efficient for a turbine. You might know they are defunct (again). A poor fellow RV-8 bother had one, it toasted. He sent it back but in the aftermath of the business failing, they have not returned his engine, which was bought and paid for!

To get a little off topic, if we would junk most of the big trucks, SUV's for personal 50 mpg vehicles (not even hybrid) we'd solve the short term gas issues and get of foreign oil. Of course attrition would need to take over but car makers still make vehicles with 18 to 25 mpg on a good day. Think about it. The current average car / light truck on us highways and roads in the USA gets 17 miles/gal! Today's average reg gas price is $3.60/gal. Even if the average gas milage of vehicles only went up to 35 mpg we, could get off of mid east (mostly). As far as gas prices, I think (know) the US & foreign oil companies and Oil cartels are capitalizing on circumstances. Supply and demand issues are more complicated because of the world wide demand from burgoning economies like China. However if we cut use in half the price would fall. Sadly my wish or theory is not likely to happen. I'm no tree hugger but we have to get real. Pain now or pain later. Future of GA?

There was local news paper article of a guy about his Bonanza and his Son who is also a pilot. They are selling the plane and will stop flying. That is sad.

[Roddzilla]

I do understand the engineering behind all of this... I meant "sip" as in barely use any. I know Innodyns claims are extraordinary. Maybe the sarcasm (towards Innodyn) in my post was not amplified enough.



Thanks though.

DR

[rv8ch]

There are people looking very seriously at electric flight. Just down the road from me Bertrand Piccard has the Solar Impulse project (http://www.solarimpulse.com/)

[RV8RIVETER]

Thanks to all, nice open discussion, just what forums are for.

I thought it would be fun to just throw out this topic and see what happens.

Yes energy is lost conversion but it makes a lot more sense in cars, where the generator engine can be tuned for one most efficient rpm and not expected to power 100% output as capacitors or batteries can make up the difference for acceleration. Cars also stop/start so the wasted energy on stopping can be reclaimed.

None of those really apply to an airplane, so we will have to wait for some revolutionary battery technology.

[647jc]

One aspect of this topic that wasn?t considered is the ability of a hybrid system to ?bank? or temporarily store power to be used in addition to the internal combustion engine output. Although we think of an airplane engine being used for somewhat constant power output compared to an automobile engine, it really isn?t. An example mission of an airplane may be to takeoff at a specific load requiring 200 HP. Once at cruise the engine would be throttled back to 65% power at which time that remaining 35% power capacity is not needed and really becomes a lump of aluminum ballast. A similar mission could be accomplished with a hybrid system incorporating a 150 HP engine and enough energy storage capacity for an additional 50 HP for say 10 minutes. Prior to takeoff you would be running your engine at full power to top off the batteries and once completed you could generate your required 200 HP (for about 10 minutes) needed for takeoff. Once in cruise mode, the engine would run at full power although only 130 HP would be needed to maintain cruise speed, the other 20 could be used to top off the batteries so you would have your 200 HP available if needed. This is just an example, the system efficiencies and weight would all have to be worked out of course for this to really be feasible along with the risk factors of not always having full power available at your demand but I think the system could be workable. Sort of like a re-usable self recharging JATO system.

[gmcjetpilot]

Remember "Helios" that hugh flying wing, unmanned solar plane, for high altitude research.
LOOK AT THE FLEX OF THE WING!

http://www.youtube.com/watch?v=5oNHD41MLMk

Its no more and broke-up in flight, into ocean, Hawaii in 2003.

http://www.cbc.ca/health/story/2003/...ios030627.html

At this time with solar cell power and elect motors this is what it takes. So the motor and cell technology would have to be much advance to fly on sun power only. Also cost?

[glenn654]

Hey Guys,
Electric power may be available sooner than anyone thinks. Check out A123 Systems, they developed the batteries for the upcoming Chevy Volt (2010), built an electric drag bike...fastest on record....appears to have good potential but I really like the sound of internal combustion.

Glenn Wilkinson