A hybrid plane based on Cessna Skymaster

[kyleb]

I don't know much about them and not affiliated, but this Ampaire "Hybrid-Electric"Skymaster 337 flew at Oshkosh in 2022. https://www.ampaire.com/

I talked with those guys at length. According to the main guy I talked with, they shut the electric motor off after takeoff and climb-out and flew the rest of the trip on the recip. Their marketing materials were "Experimental Hybrid aircraft Flew to Oshkosh from the West Coast with one stop.", or something like that. They didn't mention that only about 10 minutes of the flight actually used the electric motor.

 

[Dan Thomas]

During the fuel crunch brought on by the OPEC oil embargo in the early '70s, airliners were being towed to the hold-short lines, where they would start their engines and then take off.

I'd be wondering about engine parameter stabilization before takeoff, with so little time between startup and full TO power.

 

[Dan Thomas]

I talked with those guys at length. According to the main guy I talked with, they shut the electric motor off after takeoff and climb-out and flew the rest of the trip on the recip. Their marketing materials were "Experimental Hybrid aircraft Flew to Oshkosh from the West Coast with one stop.", or something like that. They didn't mention that only about 10 minutes of the flight actually used the electric motor.

Seems like mostly a waste of time and money, then. Surely not yet another investment scam?

 

[tspear]

This project/company looks a little more thought out than many of the others. Will they eventually succeed? It is possible, likely requires a lot money.
In any case, they are looking to utilize a proven air frame to develop the power plant technology. This reduces the risk and variables significantly; and likely increases the chance for success.

Tim

 

[Albany Tom]

Seems like mostly a waste of time and money, then. Surely not yet another investment scam?

People in the venture capital and aircraft industries are much too ethical to do anything like that.

Did I sound convincing?

 

[Tantalum]

Is there any reason that several of these designs make use of extremely aerodynamically dirty planes? I mean I love the sky master but it's not known for being an efficient slippery airplane, especially not with a belly pod. Same is true for that beaver someone was making electric

You would think starting with a Lancaire frame or something similar (TTx?) would make more sense

 

[Salty]

Is there any reason that several of these designs make use of extremely aerodynamically dirty planes? I mean I love the sky master but it's not known for being an efficient slippery airplane, especially not with a belly pod. Same is true for that beaver someone was making electric

You would think starting with a Lancaire frame or something similar (TTx?) would make more sense

There’s nowhere to shove hundreds of pounds of batteries in a lance air.

 

[Tantalum]

^ I remain an electric airplane skeptic..

 

[kyleb]

Seems like mostly a waste of time and money, then. Surely not yet another investment scam?

It makes no practical sense at this time. Now, as a fundraiser or a way to lure the investors, it may lure a few. Then again, in 20 years they may rule the world it the technology matures.

 

[Joepilotmsp]

Well, those are damn good reasons!
I figured this more for jet airliners, who have lots of ground movement and waiting around at big airports. Driven wheels seen more efficient than props or jets, and an electric would let you use the power generated by the jet engines.
But, you may have just demonstrated why I am not an engineer.

I still think it’s really interesting, out of the box thinking. Not an engineer either, but think if the drive motors could be powered by the APU, engines left off till just ready for takeoff and shut down after landing and clear of runway…. Traction is easily solved by putting motor(s) on mains. Using APU, may not even need extra batteries. Sure I’m missing a cubic butt load on technical rocket doctor stuff about this.

 

[tspear]

Is there any reason that several of these designs make use of extremely aerodynamically dirty planes? I mean I love the sky master but it's not known for being an efficient slippery airplane, especially not with a belly pod. Same is true for that beaver someone was making electric

You would think starting with a Lancaire frame or something similar (TTx?) would make more sense

The Beaver was likely selected because the airline already flies them. They are short haul, and water based.
As for the Skymaster, for payload capacity and flexibility to a tri motor situation it is very cheap to acquire. This platform is to prove/workout the powertrain system it is not a (or at least publicly stated) a development goal. A slippery plane is actually a disadvantage since you would be going significantly faster or have less load on the engines. (Speed when needing to burn hours near an airport is not an advantage).

Tim

 

[Tantalum]

The Beaver was likely selected because the airline already flies them. They are short haul, and water based.
As for the Skymaster, for payload capacity and flexibility to a tri motor situation it is very cheap to acquire. This platform is to prove/workout the powertrain system it is not a (or at least publicly stated) a development goal. A slippery plane is actually a disadvantage since you would be going significantly faster or have less load on the engines. (Speed when needing to burn hours near an airport is not an advantage).

Tim

Thanks, so the platform is more out of necessity in this case to test their powertrain and proof of concept. If any of these ventures (as of now) look viable, I'd have to put my money on the Alice folks

It would be fun to be an engineer on one of these teams. Even if electric / battery technology is not there yet (nor may it ever be) it has to be rewarding to be working on something unconventional

 

[Dan Thomas]

I still think it’s really interesting, out of the box thinking.

It's not out of the box. That idea has been around for 50 years.

I did a bit of digging and found this: https://en.wikipedia.org/wiki/EGTS

The system weighs 660 pounds. Airlines hate stuff like that. That's the weight of three or four or five more paying passengers, or more freight, and the money for those fares might easily outweigh any fuel savings. A few empty seats in an airliner can mean no profit. It's a narrow-margin business.

Freight must make more money than people. They discourage checked baggage by charging for it. They want that baggage compartment for freight and mail and whatnot, and that stuff doesn't complain and doesn't need feeding and coddling and doesn't get rude and unmanageable.

 

[Dan Thomas]

It would be fun to be an engineer on one of these teams. Even if electric / battery technology is not there yet (nor may it ever be) it has to be rewarding to be working on something unconventional

I'd rather be working on stuff that I knew was going to work and not eventually face public ridicule and lawsuits by investors. Any of the machinery I invented and built worked successfully right off the bat, or needed a bit of tweaking. I didn't build anything that needed a component that didn't exist. My employer might not have appreciated the loss of time and money.

 

[tspear]

It's not out of the box. That idea has been around for 50 years.

I did a bit of digging and found this: https://en.wikipedia.org/wiki/EGTS

The system weighs 660 pounds. Airlines hate stuff like that. That's the weight of three or four or five more paying passengers, or more freight, and the money for those fares might easily outweigh any fuel savings. A few empty seats in an airliner can mean no profit. It's a narrow-margin business.

Freight must make more money than people. They discourage checked baggage by charging for it. They want that baggage compartment for freight and mail and whatnot, and that stuff doesn't complain and doesn't need feeding and coddling and doesn't get rude and unmanageable.

Actually no. Checked bag fees were a way to increase the total fair per traveler; and have worked extremely well.

Tim

 

[nauga]

I'd rather be working on stuff that I knew was going to work and not eventually face public ridicule and lawsuits by investors. Any of the machinery I invented and built worked successfully right off the bat, or needed a bit of tweaking. I didn't build anything that needed a component that didn't exist. My employer might not have appreciated the loss of time and money.

It sounds like you were involved with production and possibly product development. *Research* and development, rapid prototyping, and advanced technologies by their nature mean not everything will be successful right off the bat or after 'a bit of tweaking'. The tech development side has been some of the most fulfilling work of my career, even if it didn't all work out. Some of the things I worked on, even some successful ones, have also been the subject of ridicule, some of it here. Criticism is more meaningful when it comes from people who understand technology maturation processes and the technology involved.

Nauga,
with pi in the sky

 

[Joepilotmsp]

It's not out of the box. That idea has been around for 50 years.

I did a bit of digging and found this: https://en.wikipedia.org/wiki/EGTS

The system weighs 660 pounds. Airlines hate stuff like that. That's the weight of three or four or five more paying passengers, or more freight, and the money for those fares might easily outweigh any fuel savings. A few empty seats in an airliner can mean no profit. It's a narrow-margin business.

Freight must make more money than people. They discourage checked baggage by charging for it. They want that baggage compartment for freight and mail and whatnot, and that stuff doesn't complain and doesn't need feeding and coddling and doesn't get rude and unmanageable.

I bet your a real hoot at a party. Calling BS on your weight claim being a total loss. It would be more than offset, IMHO, by the savings in fuel alone not to mention needing less ground support. Maybe I’m wrong and if so hopefully someone who flys the big birds and knows the fuel numbers can chime in. I’m a cop with wings, (or a flying pig if you prefer lol), it’s my opinion only and your mileage may vary. Thanks for the wiki link. Very interesting. Maybe the system isn’t ready yet for prime time, but I’m glad people are indeed thinking out of the box. Stop being such a Danny Downer and have a Happy New Year Dan!

 

[Dan Thomas]

I bet your a real hoot at a party. Calling BS on your weight claim being a total loss. It would be more than offset, IMHO, by the savings in fuel alone not to mention needing less ground support. Maybe I’m wrong and if so hopefully someone who flys the big birds and knows the fuel numbers can chime in. I’m a cop with wings, (or a flying pig if you prefer lol), it’s my opinion only and your mileage may vary. Thanks for the wiki link. Very interesting. Maybe the system isn’t ready yet for prime time, but I’m glad people are indeed thinking out of the box. Stop being such a Danny Downer and have a Happy New Year Dan!

I'm old enough to have seen a lot of ideas proposed and tried, only to see them disappear. 2023 will be 50 years since I started flying. What's your experience?

The proof will be in the pudding, as they used to say. If it's viable, and the fuel savings outweighs the system weight, and if it doesn't require a bigger APU (representing added cost and fuel burn), it might catch on. It will take considerable horsepower to move an airliner at gross weight at the claimed 20 knots, especially in a headwind, up any slight slope, or on even a little snow.

At least it's being done by Honeywell and Safran, both reputable outfits. Safran, though, was the developer of the SMA diesel aircraft engines that had some serious teething problems (I worked on repairing one 12 years ago, in a 182), and they sold the whole thing to the Roder group a couple of years ago. At the time I was working on it, SMA had 50 engines flying worldwide, after they had spent one billion US dollars on it. Pilots and owners were demanding diesel power, but most weren't willing to pay the $80K at the time, plus conversion costs, for it. Engine development is terribly expensive. It's why most Lycomings and Continentals were mostly evolutionary designs, avoiding clean-sheet stuff that gets so expensive and can be troublesome, like the Continental Tiara and their Voyager series. Both failed.

 

[Joepilotmsp]

I'm old enough to have seen a lot of ideas proposed and tried, only to see them disappear. 2023 will be 50 years since I started flying. What's your experience?

The proof will be in the pudding, as they used to say. If it's viable, and the fuel savings outweighs the system weight, and if it doesn't require a bigger APU (representing added cost and fuel burn), it might catch on. It will take considerable horsepower to move an airliner at gross weight at the claimed 20 knots, especially in a headwind, up any slight slope, or on even a little snow.

At least it's being done by Honeywell and Safran, both reputable outfits. Safran, though, was the developer of the SMA diesel aircraft engines that had some serious teething problems (I worked on repairing one 12 years ago, in a 182), and they sold the whole thing to the Roder group a couple of years ago. At the time I was working on it, SMA had 50 engines flying worldwide, after they had spent one billion US dollars on it. Pilots and owners were demanding diesel power, but most weren't willing to pay the $80K at the time, plus conversion costs, for it. Engine development is terribly expensive. It's why most Lycomings and Continentals were mostly evolutionary designs, avoiding clean-sheet stuff that gets so expensive and can be troublesome, like the Continental Tiara and their Voyager series. Both failed.

Lots of truth in what you said. Like I’ve said, I ain’t no rocket doctor. If this don’t get it, I hope something else will. Something, some way, some how needs to. Don’t know much about putting a diesel in an aircraft. I can tell you the one in my Kabota tractor weighs a cubic butt load and that’s only 55hp. Seems a tall order putting one on enough of a diet to make it not super heavy and as you said, it’s costs bank. Luckily there are far better minds than mine at work on it. Happy New Year Dan.

 

[Albany Tom]

The British government built an airship with diesel engines in the 1920s. It burned up over France on its maiden flight I believe. Nevil Shute wrote about it, and more or less why interfering with the free market and natural evolution of engineering and science might not be a good idea. It's a good book.

https://www.amazon.com/Slide-Rule-Nevil-Shute/dp/1842322915

It's been almost 100 years since then, so maybe it makes more sense now. (Diesel engines in aircraft I mean. The other bit is still true.)

 

[kyleb]

The British government built an airship with diesel engines in the 1920s. It burned up over France on its maiden flight I believe.

The engines were not seen as a causal factor (or potential causal factor) in the crash of the R101. The most likely cause of the crash was a ruptured hydrogen cell which caused the ship to pitch down and crash.

 

[Albany Tom]

The engines were not seen as a causal factor (or potential causal factor) in the crash of the R101. The most likely cause of the crash was a ruptured hydrogen cell which caused the ship to pitch down and crash.

I didn't mean to imply that the engines caused the crash. I meant to suggest that the airship was designed improperly, constructed poorly, and pushed into service too quickly, and it was. The poor design included the use of diesel engines. But nearly 100 years later the math may have changed.

 

[kyleb]

I didn't mean to imply that the engines caused the crash. I meant to suggest that the airship was designed improperly, constructed poorly, and pushed into service too quickly, and it was. The poor design included the use of diesel engines. But nearly 100 years later the math may have changed.

No doubt the airship was poorly designed (or maybe poorly executed), but the engines on many (most?) airships were diesels. Hindenburg, Graf Zeppelin, Akron, Macon, R101, etc. were all powered by diesels. I don't think the engines were factors in the loss of any of the ships that went down.

 

[Dan Thomas]

Don’t know much about putting a diesel in an aircraft. I can tell you the one in my Kabota tractor weighs a cubic butt load and that’s only 55hp. Seems a tall order putting one on enough of a diet to make it not super heavy and as you said, it’s costs bank. Luckily there are far better minds than mine at work on it. Happy New Year Dan.

This is the SMA 305-230 diesel. It weighs only about 40 pounds more than the Continental O-470 it replaced in the 182Q, and that includes the turbo. Same 230 HP, but at 2200 RPM instead of 2600. Full FADEC controls with mechanical backup.

 

[Albany Tom]

No doubt the airship was poorly designed (or maybe poorly executed), but the engines on many (most?) airships were diesels. Hindenburg, Graf Zeppelin, Akron, Macon, R101, etc. were all powered by diesels. I don't think the engines were factors in the loss of any of the ships that went down.

Agree on engines not being a problem on most airships. And you're right, diesels were often used. From a quick Wiki search, the German airships were powered by German diesel engines (D-Benz), the Akron and Macon by German gasoline engines (Maybach). The R101, the poor one, had what sounds like a miserable diesel engine that had some issues. The R100, the "good one", had a Rolls Royce gasoline engine.

 

[Kiddo's Driver]

Use the electric to regen into the battery on the way down much like an air brake.

 

[Salty]

Use the electric to regen into the battery on the way down much like an air brake.

Sure. 5 minutes of regen, AND you get to go slower with all the issues that might cause. That’ll make it viable.

 

[Dan Thomas]

Sure. 5 minutes of regen, AND you get to go slower with all the issues that might cause. That’ll make it viable.

Yup. It'll make a steeper glide, so you'd have to get closer to the airport before commencing a descent, meaning that more power is consumed in maintaining altitude while getting closer. Where's the gain?

 

[tspear]

Yup. It'll make a steeper glide, so you'd have to get closer to the airport before commencing a descent, meaning that more power is consumed in maintaining altitude while getting closer. Where's the gain?

Higher altitude has less drag. So less energy will be consumed, in theory.
Plus a bomber approach reduces potential sound disturbances of the airport neighbors.
Use generation in place of high drag devices like speed brakes.

Between the three, the second one will help GA. The first one, might be measurable enough to make up for energy loss on conversion of mechanical energy to chemical. Somehow I doubt it, but maybe. The third one is on the only one where the generation would really come into its own.

Tim

 

[Salty]

Higher altitude has less drag. So less energy will be consumed, in theory.
Plus a bomber approach reduces potential sound disturbances of the airport neighbors.
Use generation in place of high drag devices like speed brakes.

Between the three, the second one will help GA. The first one, might be measurable enough to make up for energy loss on conversion of mechanical energy to chemical. Somehow I doubt it, but maybe. The third one is on the only one where the generation would really come into its own.

Tim

You wouldn’t get enough back to warrant the weight of the circuitry required, which also isn’t much. It only works on cars in stop and go traffic where you spend half your time braking. They wouldn’t do it in cars either if every drive were on a freeway at 65 mph and only slowing on arrival. Regen braking isn’t all that efficient either, if it were, your range in stop and go traffic would be amazing. In an airplane it would be even worse. Using the propeller to regen? it doesn’t even pass a basic physics sniff test.

 

[Dan Thomas]

Using the propeller to regen? it doesn’t even pass a basic physics sniff test.

Especially since the airflow through the prop, while not "backwards," is against the cambered side, exactly opposite to what is really needed for any sort of regen. In other words, the angle of attack is very negative. Big drag even without trying to milk it for regen.