No. The only change in L/D is when the props windmills or is stuck.

Tim

Hell,,,,just start from the beginning of this thread! You would think that as pilots we would give it a thumbs up. Shame!![/quote]

If he said 400kts, 5000nm range for $50,000, would you give it a thumbs up? Probably not. Because it can't be done with existing technology.

I don't think people are bashing the idea of working on a new type of airplane. I think what is making people critical is that this guy appears to be operating in the same orbit as Paul Moller.

A Velocity TXL-RG is the same basic design. Although from an aerodynamic perspective, the Raptor looks much less aerodynamic.

I don't know much about the details of gas vs. diesel engine efficiency. But I do know that a diesel engine in the exact same car as a gasoline engine, can go a little bit further on the same amount of fuel. Say 10%. Yet this plane is going to go over three times further with only 20 gallons more fuel at the same speed and a higher gross weight? That doesn't sound right. If that were the case, it would seem there would a lot more diesel engines on airplanes.

As for the price, a fastbuild Velocity is about $90,000. And doesn't include engine, electrical or avionics. And they've been building them for years so if there's a way to make it cheaper, they would probably be doing it. The Raptor is carbon fiber as opposed to fiberglass and is going to sell for $130,000 complete?

Then you look at some of the design and construction details. I think it was the shimmy damper where he used the wrong type of oil and stated: "I guess I should have read the instructions". Really???

Or in one video where you could see electrical wires laying over moving control cables?

Another thing that caught my attention was when I saw he was making plugs and molds first. I guess if he was Lockheed or Boeing with wind tunnels and rooms full of engineers that would make sense. But he has no idea how (or even if) this design will fly or how it will fly. He may find out that the canard has too much lift. Or that the winglets are fluttering and the rudders have to be shimmed halfway out to stop the flutter. Which means new plugs and molds. To me that seems backwards. I would think that first you verify the design. Then make the plugs and molds for production.

I would be happy to see anyone come out with a 5 seat, 250kt, 3,000nm airplane for $130K. But this ain't it. This (as it stands now) is just another SkyCar.

No. The only change in L/D is when the props windmills or is stuck.

Tim

You're right, I blew the math on that one! I'll claim sleep deprivation.......

CAD, CFD and flying a scale model were his verification, but it certainly seems like he could have done more of it. Maybe he did, but just didn't make videos of it?

What the heck are you bloviating on now? The Raptor is not going to fly at 300 knots for 3600 miles dead stick. Maybe I am wrong and you can please explain why?

You continue to not answer any relevant questions posed to you, yet you expect people to keep answering your misguided and irrelevant questions. Hmmm.

If you have the guts, show us how smart YOU are. What values have you estimated for Cdp, Cdi and BSFC? How did you come up with your estimates and why do you think they are reasonable and likely to be achieved by the team developing the Raptor?

I think you won’t post answers to these questions because you have no idea what you are talking about. I think you are incapable of answering these questions and you are only here to criticize others. Maybe I am wrong and you can please explain why?

Neither will it fly for very long. I give him 20-30 hrs before that Frankenstein engine craters in. Just hope no one dies when it happens.

Neither will it fly for very long. I give him 20-30 hrs before that Frankenstein engine craters in. Just hope no one dies when it happens.

What the heck are you bloviating on now? The Raptor is not going to fly at 300 knots for 3600 miles dead stick. Maybe I am wrong and you can please explain why?

You continue to not answer any relevant questions posed to you, yet you expect people to keep answering your misguided and irrelevant questions. Hmmm.

If you have the guts, show us how smart YOU are. What values have you estimated for Cdp, Cdi and BSFC? How did you come up with your estimates and why do you think they are reasonable and likely to be achieved by the team developing the Raptor?

I think you won’t post answers to these questions because you have no idea what you are talking about. I think you are incapable of answering these questions and you are only here to criticize others. Maybe I am wrong and you can please explain why?

Are you saying that he will be able to feather that prop with a dead engine???

I thought the governor on that plane was oil pressure driven.

I don't think the engine is the issue here.

A thread and video on a guy with a Long EZ. Had an O-235 Lycoming he flew in it for ten years. Yanked it and put a small block, direct drive Ford in it. Runs it flat out racing all the time (Something we have been assured here over and over you can not do with just a "car engine.") and has flown it cross country for years..

http://forum.canardaviation.com/showthread.php?t=5027

https://www.youtube.com/watch?v=EnmI-9qMFXs


Given

1.) The different torque curves in a diesel vs a gas engine. (Can turn the engine at slower RPM per torque generated)

2.) The reduction in prop speed using the re-drive. (Can swing a larger diameter prop at lower RPM and lower pitch, thus getting a more efficient bite (i.e Lower Reynold's number flow))

3.) And a the turbo (Enough air at altitude?)

Peter's choices start to make a lot of sense.

Curious to see how the re-drive turns out long term. Biggest issues being the delta in alignment given the drive side is somewhat flexible mounted (Engine mount grommets) vs the prop pulley being mounted directly to the frame.

Are you saying that he will be able to feather that prop with a dead engine???

I thought the governor on that plane was oil pressure driven.

Way off.

• Carson speed is best L/D * 1.32 This is the least wasteful speed. e.g. the best forward speed you can get with the least wasteful fuel usage.
• Best range no wind is at best L/D
• As for an changing polar, you are obsessed on pretty graphs that have limited to no practical use to a pilot
• You seem to care about dead stick. Not sure how this matters. If the engine is not producing thrust then the plane is not going to continue flying.
• As a general rule of thumb; most GA powered aircraft are between 8:1 and 12:1 glide ratio. Not even close to 20:1. Above 12:1 you really need to be looking at tandem designs like sail/glider planes to have the minimal square plate area.

Tim

I know the engine is not the issue! Its a beast......and I can explain owning one.

The older I get the more I HATE negative people! Pessimistic!!!!!! .......unbelievable the way some think these days. I am so glad we all don't think like that.......

I'd never own one but I am going to thumbs up the guy for trying, vs sitting on BT and being a pessimistic pilot.

Way off.

• Carson speed is best L/D * 1.32 This is the least wasteful speed. e.g. the best forward speed you can get with the least wasteful fuel usage.
• Best range no wind is at best L/D
• As for an changing polar, you are obsessed on pretty graphs that have limited to no practical use to a pilot
• You seem to care about dead stick. Not sure how this matters. If the engine is not producing thrust then the plane is not going to continue flying.
• As a general rule of thumb; most GA powered aircraft are between 8:1 and 12:1 glide ratio. Not even close to 20:1. Above 12:1 you really need to be looking at tandem designs like sail/glider planes to have the minimal square plate area.

Tim