Raptor Aircraft

kyleb said:
He's shrugged off more concerns than I can count. Bolt failure in the drive mechanism? Shucks, happens to everybody.

This is the protracted, ground based version of one of those videos where a pilot freezes up and rides the thing into a smoking hole instead of punching out.

At what point do you realize you're in unrecoverably over your head and call the whole thing off? He can do that now and nobody gets hurt/killed. He could even retrench and bolt a Lycoming or a Continental on the back and prove the concept while he gets professional help on the homebrew engine/redrive. That would greatly decrease the chances this thing ends up in a peanut field at the end of one of the first 5 flights.
Click to expand...
Before a decision could be made it would be necessary to find issues with the installed power plant. From the outside looking in and with the limited information we have it would seem to be a reasonable conclusion. We do not have all the data regarding what’s hanging on the firewall. Hopefully whoever the local talent is that he’s hiring will be engaged in a robust evaluation before a flight is attempted.
 
kyleb said:
He's shrugged off more concerns than I can count. Bolt failure in the drive mechanism? Shucks, happens to everybody.

This is the protracted, ground based version of one of those videos where a pilot freezes up and rides the thing into a smoking hole instead of punching out.

At what point do you realize you're in unrecoverably over your head and call the whole thing off? He can do that now and nobody gets hurt/killed. He could even retrench and bolt a Lycoming or a Continental on the back and prove the concept while he gets professional help on the homebrew engine/redrive. That would greatly decrease the chances this thing ends up in a peanut field at the end of one of the first 5 flights.
Click to expand...
Another option is to bolt the novel powerplant onto a proven airframe. The Raptor is clearly not going to meet its performance goals with a conventional powerplant: 230 KTAS on 7 gph, FL250 ceiling, 1100-foot takeoff roll, 1500 pound useful load, 3600 nm range, etc. Those goals will require a novel airframe and a novel powerplant. But testing the two separately does seem like a good idea.

Buy a Velocity and do an engine swap between it and the Raptor. Once both of them are flying consistently and safely, re-swap the engines, and sell one of the planes.
 
I’m not a driveline engineer, but I know a few. Having bolts back out this soon, tells me he has a harmonic problem in the redrive that will make it self destruct sooner rather than later.google drive line issues with the bd-5 to learn a lot about the problems with redrives.
 
unsafervguy said:
I’m not a driveline engineer, but I know a few. Having bolts back out this soon, tells me he has a harmonic problem in the redrive that will make it self destruct sooner rather than later.google drive line issues with the bd-5 to learn a lot about the problems with redrives.
Click to expand...

As more knowledgeable people than me pointed out in another forum, you don't use bolts to hold shaft alignment. You step the two mating surfaces so their centerline is defined by a mated flange or some other fixed mechanism. Then, you bolt things together to maintain flange to flange friction. Or you could put lugs on one flange, with matching holes on the other flange (like we do with propellers).
 
midwestpa24 said:

Another new video. Another minor issue. Obviously easy to fix and overcome, but with an all new untested powerplant built by someone without experience in aircraft powerplants, you have to wonder how many other little things like this exists waiting to be found.
Click to expand...

I love the “I thought if they backed out they’d just stop against the plate”...

Gee, or you could’ve safety wired or used some other mechanical locking mechanism and avoid the problem...

Those bolts also looked like something from the Lowe’s hardware section...
 
midwestpa24 said:

Another new video. Another minor issue. Obviously easy to fix and overcome, but with an all new untested powerplant built by someone without experience in aircraft powerplants, you have to wonder how many other little things like this exists waiting to be found.
Click to expand...

Did anyone else catch the plastic water bottle taped to the engine/prop mount at about the 12:16 mark?
 
May be the safe way to test flight this plane is wire it up with servo’s and remote fly it like a drone.
 
NordicDave said:
May be the safe way to test flight this plane is wire it up with servo’s and remote fly it like a drone.
Click to expand...

or just push it out in the grass and set it on fire to get it over with. He could wait for winter and bring some good bourbon. Just have to stay upwind. The fumes wouldn’t be nice.
 
Racerx said:
Yep. Thought I was the only one. Painters masking tape. This dude is a founding member of there I fixed it.
Click to expand...
That was after the engine was half apart. I saw it and assumed it was a catch bottle for a hose that had to be disconnected during disassembly. If that thing was there during flight, well, just wow.
 
So how does this work? People who put deposits down get their money back at some point? Or is that money already gone, spent on R&D?
 
Tarheelpilot said:
I believe all the deposit money is in an escrow account. Not 100% sure about it though...
Click to expand...

I think there are two types of money involved. Investor money and escrow money. My sense is there is a milestone event (first flight?) where the escrow money moves from escrow to Peter/Raptor.
 
Not sure if that's how this particular escrow service works. These are deposits for future orders. I would think that if the Raptor gets certified and when your spot comes up, your deposit-in-escrow is applied to the initial payment. If you decide not to proceed, your deposit is forfeited. From what I've seen, Peter has been legit on how the escrow accounts are handled. The angel investors who have funded the design and build, of course, have no protections on those funds. Like venture capital.
 
dfw11411 said:
Not sure if that's how this particular escrow service works. These are deposits for future orders. I would think that if the Raptor gets certified and when your spot comes up, your deposit-in-escrow is applied to the initial payment. If you decide not to proceed, your deposit is forfeited. From what I've seen, Peter has been legit on how the escrow accounts are handled. The angel investors who have funded the design and build, of course, have no protections on those funds. Like venture capital.
Click to expand...

Those angel investors must have money to burn. Has there _ever_ been an aviation business that would be profitable for angel investors? I mean 99/100 fail, so you need the “winners” to be HUGE.
 
dfw11411 said:
Not sure if that's how this particular escrow service works. These are deposits for future orders. I would think that if the Raptor gets certified and when your spot comes up, your deposit-in-escrow is applied to the initial payment..
Click to expand...

The Raptor isn't planned to ever be certified. But I'm sure there is a milestone event out there somewhere. I've been puzzled about how/why Peter banged the drum so hard when the thing skipped off the ground for a half second a few weeks ago. "First flight, woohoo!". Sorry, no. The General Lee from Dukes of Hazzard had infinitely more airtime.
 
Salty said:
That was after the engine was half apart. I saw it and assumed it was a catch bottle for a hose that had to be disconnected during disassembly. If that thing was there during flight, well, just wow.
Click to expand...

You mean you aren't using a water bottle for a radiator overflow container in your car? I thought they were common.

He could go to something more exotic, like a hospital bed urinal bottle.
 
3393RP said:
You mean you aren't using a water bottle for a radiator overflow container in your car? I thought they were common.

He could go to something more exotic, like a hospital bed urinal bottle.
Click to expand...

Give him time. At some point he’ll screw up the tuning on the engine, then turn to diesel truck forums and have someone tell him he just needs to run a bottle of diesel injector cleaner through it under load...poof, instant replacement overflow bottle...
 
In past 20 pages what could possibly be said that hasn't already?

giphy.gif
 
In his video from Saturday at about the 5:20 mark of his panel in the lower right corner and the Altimeter keep increasing was just about 300 feet when I stopped but started at about 247. I don't fly glass so asking if this is normal behavior?

 
NHWannabe said:
In his video from Saturday at about the 5:20 mark of his panel in the lower right corner and the Altimeter keep increasing was just about 300 feet when I stopped but started at about 247. I don't fly glass so asking if this is normal behavior?
Click to expand...

Only if there's something wrong with your static system. :eek::eek:
 
NordicDave said:
In past 20 pages what could possibly be said that hasn't already?

giphy.gif
Click to expand...

jrcox19 said:
Almost every time he posts a new video, there's something new and stupid that's happened. It's amazing really.
Click to expand...

We all know it's a failed execution. The fate is self-evident. Who still needs convincing on this point? A guess 20 more pages we'll all be a little smarter on the Raptor. :dunno:
 
I must’ve missed it in one of the earlier posts/videos...why is the nose sharp (and in my opinion, the way I’d expect it to look) in the animated intro to the video, yet so short and blunt on the aircraft?
 
NordicDave said:
We all know it's a failed execution. The fate is self-evident. Who still needs convincing on this point? A guess 20 more pages we'll all be a little smarter on the Raptor. :dunno:
Click to expand...

It's because the saga is on going. Everytime a new video comes out this thread comes to life, usually in awe at the new level of incompetence shown.
 
midwestpa24 said:
It's because the saga is on going. Everytime a new video comes out this thread comes to life, usually in awe at the new level of incompetence shown.
Click to expand...
You just can't look away. When I first found this thread I thought the people piling on Raptor were a bunch of air-chair engineers. It became readily apparent after watching the videos and reading more into it that much of the concerns are well founded.
 
iamtheari said:
Buy a Velocity and do an engine swap between it and the Raptor. Once both of them are flying consistently and safely, re-swap the engines, and sell one of the planes.
Click to expand...

The numbers don't work, as the Velocity is 1300 pounds lighter - empty weight - than the Raptor (1900 vs 3200ish).
 
Tarheelpilot said:
Before a decision could be made it would be necessary to find issues with the installed power plant. From the outside looking in and with the limited information we have it would seem to be a reasonable conclusion. We do not have all the data regarding what’s hanging on the firewall. Hopefully whoever the local talent is that he’s hiring will be engaged in a robust evaluation before a flight is attempted.
Click to expand...

I've read several comments about the dual turbochargers that are installed in a serial configuration on the Raptor's Audi diesel engine, all of them negative, but also lacking clear engineering reasons why they weren't suitable for the application.

That changed when I came across a post in another forum. The writer is obviously well versed in turbocharger concepts. His knowledge provides a well thought out analysis of why the installation on the Raptor is not only improper, it's also dangerous. With this post, and a few follow ups, it becomes clear that it's just a matter of time before the engine will fail. Anyone with a basic grasp on gas mechanics and thermodynamic principles can understand the author's reasoning.

Unsurprisingly, when the author makes the same post on Peter's YouTube channel, it is dismissed as just more criticism by haters. Peter's answer clearly illustrates he has no concept of thermodynamics, how gas compression works, or the difference between gas volume and mass.

This is a damning indictment of Peter's lack of knowledge, and a perfect example of how he routinely ignores well founded criticism of the aircraft's design and execution.



https://www.homebuiltairplanes.com/forums/threads/raptor-composite-aircraft.24721/post-547398
 
I just assumed the engine was basically Audi-stock besides the ECM and the drive.
 
NHWannabe said:
In his video from Saturday at about the 5:20 mark of his panel in the lower right corner and the Altimeter keep increasing was just about 300 feet when I stopped but started at about 247. I don't fly glass so asking if this is normal behavior?
Click to expand...
No, it's not. His static port is in a low pressure area. I believe that he actually moved it to INSIDE the cabin. So in addition to an increase in indicated altitude, he is also seeing a higher than actual airspeed indication.
 
3393RP said:
I've read several comments about the dual turbochargers that are installed in a serial configuration on the Raptor's Audi diesel engine, all of them negative, but also lacking clear engineering reasons why they weren't suitable for the application.

That changed when I came across a post in another forum. The writer is obviously well versed in turbocharger concepts. His knowledge provides a well thought out analysis of why the installation on the Raptor is not only improper, it's also dangerous. With this post, and a few follow ups, it becomes clear that it's just a matter of time before the engine will fail. Anyone with a basic grasp on gas mechanics and thermodynamic principles can understand the author's reasoning.

Unsurprisingly, when the author makes the same post on Peter's YouTube channel, it is dismissed as just more criticism by haters. Peter's answer clearly illustrates he has no concept of thermodynamics, how gas compression works, or the difference between gas volume and mass.

This is a damning indictment of Peter's lack of knowledge, and a perfect example of how he routinely ignores well founded criticism of the aircraft's design and execution.



https://www.homebuiltairplanes.com/forums/threads/raptor-composite-aircraft.24721/post-547398
Click to expand...

Thanks for the post. I had heard of compound turbos from my days owning a diesel truck, but never got in depth. Interesting stuff.
 
Anyone object to the notion that his measured runout was acceptable on the damper plate? That much runout on a rotating component seems excessive to me...
 
Omalley1537 said:
Anyone object to the notion that his measured runout was acceptable on the damper plate? That much runout on a rotating component seems excessive to me...
Click to expand...
Based on the video, it appears to be within the specifications for that part in this installation. The spec calls for runout of no more than 2.3 metric rat's asses, and his reading of the gauge gave a little less than 1 metric rat's ass.

Seriously, I am no expert on rotating parts that go something like 6,000 rpm like this, but I would have a lot less fun driving my car if my brake discs that spin maybe 1,500 rpm looked like that.
 
iamtheari said:
Based on the video, it appears to be within the specifications for that part in this installation. The spec calls for runout of no more than 2.3 metric rat's asses, and his reading of the gauge gave a little less than 1 metric rat's ass.

Seriously, I am no expert on rotating parts that go something like 6,000 rpm like this, but I would have a lot less fun driving my car if my brake discs that spin maybe 1,500 rpm looked like that.
Click to expand...

agreed. My work car was subject to a TSB for harmonic balancers slipping between the inner hub and outer ring. The runout was very noticeable when the engine was running and it still wasn’t as bad as what he’s showing.

He dismisses it as allowable “for a rubber part”...perhaps it is for the part itself, but that should be a trigger to find a part of a different design/materials in my opinion.
 
It's like watching a CFIT with the pilot confidently telling you each time why he's right when everyone else can see the mountain he's about to plow into. With the amount of problems this guy finds each time it taxies fast I can only imagine what horrors will surface when this thing gets in the air

I can picture it now
"the left canard stopped responding, looks like the bent bolt slipped slipped, I decided against safety wiring these parts to save weight. Some pretty bad vibrations, let me make a nice cad drawing then ignore it and glue some quarters to a random part of the right aileron for balancing"
 
Tantalum said:
It's like watching a CFIT with the pilot confidently telling you each time why he's right when everyone else can see the mountain he's about to plow into. With the amount of problems this guy finds each time it taxies fast I can only imagine what horrors will surface when this thing gets in the air

I can picture it now
"the left canard stopped responding, looks like the bent bolt slipped slipped, I decided against safety wiring these parts to save weight. Some pretty bad vibrations, let me make a nice cad drawing then ignore it and glue some quarters to a random part of the right aileron for balancing"
Click to expand...

You forgot the part where he deletes the comments trying to point out the real problem...
 
You must log in or register to reply here.
Back
Top