Shameless update from Dale Kramer

On Thursday, March 17, 2016 at 10:36:06 PM UTC-4, 2G wrote:
Your "design" looks to have a very high disk loading. What CAD analysis (if any) have you done of this design, and what CAD tools did you use?

Tom

I assume you are asking about rotor disk loading in hover mode which is about 18 lbs.ft^2

And my hover lift efficiency is about 5 hp/lb

I don't see either of those being 'high' unless you start comparing the design out of category. I believe the nearest category for hovering should be multirotor. In the multirotor category I would expect it to 'above normal' because I use the same props/rotors to achieve static thrust for hover and for traction thrust at high airspeeds during cruise, so compromises are made for both flight conditions.

I am a little confused in that I traditionally think of CAD programs as simply the program used to draw a design on a computer. From the question I think you might mean CAE or CFD or simply analysis tools like XFLR5.

In any case I used XFLR5 for aerodynamics analysis, Javaprop for prop analysis and I have not done any CFD yet.

On Friday, March 18, 2016 at 5:27:44 AM UTC-7, DaleKramer wrote:
On Thursday, March 17, 2016 at 10:36:06 PM UTC-4, 2G wrote:
Your "design" looks to have a very high disk loading. What CAD analysis (if any) have you done of this design, and what CAD tools did you use?

Tom

I assume you are asking about rotor disk loading in hover mode which is about 18 lbs.ft^2

And my hover lift efficiency is about 5 hp/lb

I don't see either of those being 'high' unless you start comparing the design out of category. I believe the nearest category for hovering should be multirotor. In the multirotor category I would expect it to 'above normal' because I use the same props/rotors to achieve static thrust for hover and for traction thrust at high airspeeds during cruise, so compromises are made for both flight conditions.

I am a little confused in that I traditionally think of CAD programs as simply the program used to draw a design on a computer. From the question I think you might mean CAE or CFD or simply analysis tools like XFLR5.

In any case I used XFLR5 for aerodynamics analysis, Javaprop for prop analysis and I have not done any CFD yet.

CAD, or computer-aided design, covers the gamut of software tools, not just basic drafting. I was thinking of aeronautical engineering tools, however. You obviously have available drafting tools.

Your disk loading is quite high, between a Super Stallion and an Osprey. This precludes an autorotate capability. Having 5 motors operating to sustain a hover represents a corresponding high failure probability with no recovery.

How would you land conventionally with propellers on the wing tips? Would they fold back?

I think it is incumbent upon you to disclose to potential investors that you are not an engineer (unless you have an aeronautical engineer on your team, of course).

1. Nowhere have I indicated that there was an auto-rotate capability.
2. I said that I traditionally think of CAD as drawing programs, I believe that is backed up by the current Wikipedia definition of CAD.
3. The answer to your folding props question is clearly stated on the link I provided. I choose let you go read it there.
4. I have also disclosed an extensive biography on the link provided and encouraged people to read it, as should you.
What is your agenda?

On Friday, March 18, 2016 at 6:03:54 PM UTC-7, DaleKramer wrote:
1. Nowhere have I indicated that there was an auto-rotate capability.
2. I said that I traditionally think of CAD as drawing programs, I believe that is backed up by the current Wikipedia definition of CAD.
3. The answer to your folding props question is clearly stated on the link I provided. I choose let you go read it there.
4. I have also disclosed an extensive biography on the link provided and encouraged people to read it, as should you.
What is your agenda?

I have no agenda, what is yours?

On Friday, March 18, 2016 at 11:27:49 PM UTC-4, 2G wrote:
I have no agenda, what is yours?

My agenda has been clearly stated, yours has not.
Your comments definitely indicate that you did not read the information at the link I provided and if you did, you did not evaluate any of in that manner that I would expect and engineer to evaluate the information.

On Saturday, March 19, 2016 at 12:11:30 AM UTC-4, DaleKramer wrote:
Your comments definitely indicate that you did not read the information at the link I provided and if you did, you did not evaluate any of in that manner that I would expect and engineer to evaluate the information.

Sorry, sometimes fingers don't type what my brain thinks

Should be:
Your comments definitely indicate that you did not read the information at the link I provided and if you did, you did not evaluate any of it in a manner that I would expect an engineer to evaluate the information.

On Friday, March 18, 2016 at 10:04:29 PM UTC-7, DaleKramer wrote:
On Saturday, March 19, 2016 at 12:11:30 AM UTC-4, DaleKramer wrote:
Your comments definitely indicate that you did not read the information at the link I provided and if you did, you did not evaluate any of in that manner that I would expect and engineer to evaluate the information.

Sorry, sometimes fingers don't type what my brain thinks

Should be:
Your comments definitely indicate that you did not read the information at the link I provided and if you did, you did not evaluate any of it in a manner that I would expect an engineer to evaluate the information.

You seem awfully defensive at answering questions for someone seeking public investment in your project. You should EXPECT critical questions such as mine. Investors DO NOT like being belittled for asking reasonable questions.. Your disk loading is SEVEN times higher than an R22; that is a HIGH disk loading.

Your material provides nothing about how this aircraft will be controlled during hover flight and transition from hovering to forward flight. I assume this will be done by thrust vectoring, but I do not know. This means that power must be reduced in some of the electric motors, exacerbating the effects of a motor failure.

5. You choose to define my rotor disk loading as 'high' with examples of air vehicles of two different categories, why?
6. There are 7 motors used during hover on the vLazair and your assumption appears to be that a failure of any single one, would have no recovery. That is incorrect. Multirotors can operate with one or more rotors disabled, depending on design.

On Friday, March 18, 2016 at 6:24:20 PM UTC-7, DaleKramer wrote:
5. You choose to define my rotor disk loading as 'high' with examples of air vehicles of two different categories, why?
6. There are 7 motors used during hover on the vLazair and your assumption appears to be that a failure of any single one, would have no recovery. That is incorrect. Multirotors can operate with one or more rotors disabled, depending on design.

It is high because it IS high. It is 5-6 times higher than an R22.

Seven motors is an even higher probability of failure. I have seen no DESIGN data (vs speculation) that indicates your "design" will function with the failure of any motor.

Let me remind you: you presented yourself initially as "shameless" self promotion. If you don't like criticism go someplace else.

On Friday, March 18, 2016 at 11:33:01 PM UTC-4, 2G wrote:
It is high because it IS high. It is 5-6 times higher than an R22.

Ok, so let us concentrate again on the rotor disk loading.
If you had evaluated the design as an engineer, then I would not have to had to assume that you were asking about rotor disk loading versus propeller disk loading. An engineering evaluation would have understood that there are two flight modes that use different disk loading calculations and the question would have been more specific.

Following that, you seem to have categorically determined that it has a very high rotor disk loading without specifying a class. When you start defining the class, you cite vehicles in 2 classes and now finally you are for some reason comparing my design only to a helicopter. It is obviously NOT a helicopter! It is not even in the Osprey tiltrotor class. The closest conventionally categorized class it could be put in is the tiltwing class and in that class it has a low rotor disk loading.

I believe if anyone should be criticized here it is not me.

Somehow we have rubbed each other the wrong way, for that I am sorry.