BeechTalk - BT - Raptor Aircraft 5 Seat Pressurized 3,600 NM Range Diesel

Username Protected · **Posted:** 16 Nov 2020, 12:53

Username Protected wrote:

You can make a lot more power than expected from diesel engines if you know what you are doing. In Europe there is a truck racing league. Earlier in my career I was a bit involved in these engine mods. In America there is a truck pikes peak race, same thing.

It's amazing what you can get out of some of these engines when the manufacturer turns a few engineers loose with no rules. 350HP road engines making 1500HP....for awhile.

It's fun. Fun to build. Fun to run the engine on a dyno. Fun to figure out what caused a failure. Fun to watch the races.

But I would NOT find it fun to fly behind such an engine.

Yeah, if he had hired a couple diesel experts, he wouldn’t be dealing with half the engine issues. Most of that work needed to be done up front so they would know what they needed for airflow to cool it. They probably wouldn’t have set it up with 170 F air being dumped on the radiator.

Username Protected · **Posted:** 16 Nov 2020, 12:57

Username Protected wrote:

How about a “boil-off” cooling system like the Galloping Ghost that crashed at Reno? That might be enough to get him around the pattern.....once.

Speaking of cooling, is that ridiculous little scoop on the top of the cabin supposed to supply all of the cooling required for the radiator, intercooler, oil cooler, A/C condenser, etc? It looks like it was designed by an artist for visual impact rather than someone concerned with whether it would actually work.

Username Protected · **Posted:** 16 Nov 2020, 13:20

Username Protected wrote:

Speaking of cooling, is that ridiculous little scoop on the top of the cabin supposed to supply all of the cooling required for the radiator, intercooler, oil cooler, A/C condenser, etc? It looks like it was designed by an artist for visual impact rather than someone concerned with whether it would actually work.

Yes, but... it seems it also can open and close some, and my understanding is that he had it in the more closed position for the first attempted flight. This was because he had not yet made a diverter that would focus the airflow onto the radiator; instead he just used the closed-over position.

Username Protected · **Posted:** 16 Nov 2020, 13:56

Username Protected wrote:

if he had hired a couple diesel experts, he wouldn’t be dealing with half the engine issues.

But they also would have told him that he couldn't get the power out of that engine that he wanted without sacrificing aircraft-level longevity and reliability. When you know you won't like the answer, don't ask.

Username Protected · **Posted:** 20 Nov 2020, 04:44

This week, we prepare to cut more holes in the fuselage and add an intercooler in the nose.

Man, this is going to be something.....

Username Protected · **Posted:** 20 Nov 2020, 08:37

Username Protected wrote:

This week, we prepare to cut more holes in the fuselage and add an intercooler in the nose.

Oh it’s not just an intercooler, it’s a $300 Brand X turbo intercooler that’s designed to transfer the heat of forced, turbocharged air to coolant lines. He’s using it for the opposite effect, and judging by the comments from others, it’s not going to work.

In the time it takes to cobble this all together, he could have sorted out the second turbocharger issue and fixed the airflow to the existing cooling system. The airplane isn’t the problem.

Username Protected · **Posted:** 20 Nov 2020, 09:42

It looks to me like the extra cooling tanks and expansion tank are becoming part of the plan moving forward not just a quick back-up to continue flight testing.

This new intercooler would be a good thing to do a flow model on. No way is he going to get significant flow through that. He assumes he'll have full ram air flow, neglecting the restriction of the intercooler and the fact that air will just go around this inlet.

Username Protected · **Posted:** 20 Nov 2020, 09:58

Username Protected wrote:

You can make a lot more power than expected from diesel engines if you know what you are doing. In Europe there is a truck racing league. Earlier in my career I was a bit involved in these engine mods. In America there is a truck pikes peak race, same thing.

It's amazing what you can get out of some of these engines when the manufacturer turns a few engineers loose with no rules. 350HP road engines making 1500HP....for awhile.

It's fun. Fun to build. Fun to run the engine on a dyno. Fun to figure out what caused a failure. Fun to watch the races.

But I would NOT find it fun to fly behind such an engine.

Did you ever run into Roger Bisher? He built an engine for an 18 wheeler that set a speed record.

Username Protected · **Posted:** 20 Nov 2020, 10:11

Username Protected wrote:

This week, we prepare to cut more holes in the fuselage and add an intercooler in the nose.

Man, this is going to be something.....

He has total disregard for weight. He's working in a vacuum.

Username Protected · **Posted:** 20 Nov 2020, 10:46

I appreciate you guys sharing the contents of each video. I can't stand to watch them anymore, it's too depressing.

Username Protected · **Posted:** 20 Nov 2020, 12:20

Username Protected wrote:

Did you ever run into Roger Bisher? He built an engine for an 18 wheeler that set a speed record.

Hi Rocky - I've heard the name not no, don't know him. I was a lab rat for this stuff. They didn't let us outside the engine test cells except for brief supervised yard exercise.

Username Protected · **Posted:** 20 Nov 2020, 12:33

Username Protected wrote:

Oh it’s not just an intercooler, it’s a $300 Brand X turbo intercooler that’s designed to transfer the heat of forced, turbocharged air to coolant lines. He’s using it for the opposite effect, and judging by the comments from others, it’s not going to work.

I only half-watched the vid...I totally missed that he's trying to use an air-to-water intercooler as a radiator...very "creative".

Username Protected · **Posted:** 20 Nov 2020, 12:49

Username Protected wrote:

He has total disregard for weight. He's working in a vacuum.

He thinks that will all be solved on the first production model. Could you imagine designing out 1000 lbs and planning on producing kits without any real testing? I love it how he is talking about the new hole in the nose and The effects at 180 knots. Mate, this thing isn’t going to do much more than the pattern.

Username Protected · **Posted:** 20 Nov 2020, 23:02

Username Protected · **Posted:** 20 Nov 2020, 23:21

Username Protected wrote:

:shrug:

You forgot one. :stir: