Shameless update from Dale Kramer

On Saturday, March 19, 2016 at 11:21:45 AM UTC-7, DaleKramer wrote:
I believe I have answered every question.

There is NO reason to compare my design to a helicopter in terms of disc loading since it does not operate like one.

I suggest to you that you read up on multirotor design and control.

I believe that this revolution of flight, over the last decade, has resulted in more multirotor controlled air vehicles flying than all other air vehicles combined.

Yes, perhaps I should mention a little more about that in the link.

I didn't say that you didn't answer the questions; it was your attitude towards me that I called you on.

Your "design" is not a revolution, just a variation on a concept that has been tried in the past and rejected by every aviation company since.

Further review caused me pause; the pilot, along with all controls and instruments, must rotate in two dimensions AND open the cockpit to the full prop down wash during the most critical phases of flight: takeoff and landing. Is this so?

On Saturday, March 19, 2016 at 6:04:23 PM UTC-4, 2G wrote:
On Saturday, March 19, 2016 at 11:21:45 AM UTC-7, DaleKramer wrote:
I believe I have answered every question.

There is NO reason to compare my design to a helicopter in terms of disc loading since it does not operate like one.

I suggest to you that you read up on multirotor design and control.

I believe that this revolution of flight, over the last decade, has resulted in more multirotor controlled air vehicles flying than all other air vehicles combined.

Yes, perhaps I should mention a little more about that in the link.

I didn't say that you didn't answer the questions; it was your attitude towards me that I called you on.

Your "design" is not a revolution, just a variation on a concept that has been tried in the past and rejected by every aviation company since.

Further review caused me pause; the pilot, along with all controls and instruments, must rotate in two dimensions AND open the cockpit to the full prop down wash during the most critical phases of flight: takeoff and landing. Is this so?

Attitude goes both ways.

I has also been said that no designs are revolutions, just variations.

In hover flight the pilots seat only ever opens a maximum of 90 degrees, the final 20 degrees is when engines are shut down. At 90 degrees, the pilots upper torso is still in the fuselage, the pilots legs from the waist down are enclosed in a secondary shell (with airbags). Airflow should be no worse than an open cockpit aircraft or a motorcycle. This is a 'sport' design and I don't expect it to appeal to the non-sporting. The pilots seat could be fully enclosed and still rotate, but I choose not to do that initially.

The controls are fly by wire so there is very little complexity in that 110 degree travel joint.

And for the record, to my knowledge, I did not says that this was a revolutionary design.

On Saturday, March 19, 2016 at 5:00:26 PM UTC-7, DaleKramer wrote:
And for the record, to my knowledge, I did not says that this was a revolutionary design.

Again, your attitude stinks! I can't fix stupid - you shouldn't be attempting a public venture, it just isn't your style.

You wrote "I believe that this revolution of flight". Case closed.

On Saturday, March 19, 2016 at 4:50:48 PM UTC-7, DaleKramer wrote:
On Saturday, March 19, 2016 at 6:04:23 PM UTC-4, 2G wrote:
On Saturday, March 19, 2016 at 11:21:45 AM UTC-7, DaleKramer wrote:
I believe I have answered every question.

There is NO reason to compare my design to a helicopter in terms of disc loading since it does not operate like one.

I suggest to you that you read up on multirotor design and control.

I believe that this revolution of flight, over the last decade, has resulted in more multirotor controlled air vehicles flying than all other air vehicles combined.

Yes, perhaps I should mention a little more about that in the link.

I didn't say that you didn't answer the questions; it was your attitude towards me that I called you on.

Your "design" is not a revolution, just a variation on a concept that has been tried in the past and rejected by every aviation company since.

Further review caused me pause; the pilot, along with all controls and instruments, must rotate in two dimensions AND open the cockpit to the full prop down wash during the most critical phases of flight: takeoff and landing. Is this so?

Attitude goes both ways.

I has also been said that no designs are revolutions, just variations.

In hover flight the pilots seat only ever opens a maximum of 90 degrees, the final 20 degrees is when engines are shut down. At 90 degrees, the pilots upper torso is still in the fuselage, the pilots legs from the waist down are enclosed in a secondary shell (with airbags). Airflow should be no worse than an open cockpit aircraft or a motorcycle. This is a 'sport' design and I don't expect it to appeal to the non-sporting. The pilots seat could be fully enclosed and still rotate, but I choose not to do that initially.

The controls are fly by wire so there is very little complexity in that 110 degree travel joint.

Your images show the legs forward in level flight, and the legs 90 degrees out of the plane in the opposite direction. I fail to see how this can be done with a rotation about just one axis. In any event, this requires a major body motion at a critical moment. Have you ever heard of "vertigo" and what causes it? This can be caused by just tilting the head down. Apparently you are completely unaware of this.

2G there is a lot of "stinking attitude" as you say here, but I am afraid its coming from you Thats not an unusual thing for this web site lol. I dont know much about mr kramer but I do know that he has not only sucessfully designed aircraft but also sold them to other folks who enjoy them. Will this project work? Who knows, there are definitely huge tecnological challenges here, and this guy is going to need help from other specialized engineers. That being said, your attitude is the type which I am sure the wright bros encountered all day long, namely folks who have'nt done squat themselves but sure can point out all the faults in another persons aspirations. Surely Dale knows this is not the forum to use for gaining serious investment capital, or for that matter "intelligent" aerodynamic advice. He appears to just be getting his ideas out into the public "air" a bit. So dude, lighten up, and at least applaude the guy for thinking outside the box.

On Friday, March 18, 2016 at 9:36:51 PM UTC-7, DaleKramer wrote:
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.

Dale - It's a pretty clever design. Thanks for sharing - gutsy move.

I expect the main reason to care about disk loading is to work out how many RPM at what propeller lift coefficient you need to produce enough total mass flow to hover. Presumably with the main engine running along with six electric motors you are within the operating parameters of the engines/props you have fitted and the thing can actually hover. It certainly appears to be a more highly loaded hovering design that a traditional single rotor helicopter in the same weight class, but I don't necessarily see that as particularly a big deal for what it's trying to do. I also expect that going to a higher disk loading than a typical conventional single rotor design will have some impact on efficiency and therefore endurance, but since you are not spending much time in vertical mode it's not a big factor for this design.. The bigger considerations here are the overall layout for prop tip clearance and commercially available brushless motor designs and the fact that you need multiple, displaced sources of thrust to control the thing in hover.

I'd have some questions about stability and control in hover mode. First, there is a fair amount of weight above the center of thrust for the electric motors - this includes the pilot and particularly the gas motor which is on a pretty long moment arm. This is a little like balancing a broomstick on the palm of your hand. You will need to counter any static or dynamic pitching moment with differential thrust on the electric motors, which could be problematic particularly in a low-speed transition between hover and forward flight when you have no aerodynamic elevator authority. Presumably the gas motor is pulling pretty hard which is stabilizing as long as you are vertical, but it doesn't provide any restoring pitch moment if you are at some intermediate pitch attitude, but not yet flying like an airplane. You'd need to use differential thrust on the electrics to keep the nose from tipping over, all while providing enough total thrust to hold hover.

A second potential issue is how to counteract the torque of the gas motor and prop, which see to be substantially larger than the electric motors and props. Since hexacopter yaw is controlled by adjusting the speed of the three clockwise turning versus three counter-clockwise turning props you'd have to have enough available angular momentum delta in three electric motors which are not on the centerline to counteract the angular momentum delta of the big gas motor which is on the centerline. I'm not sure how much being off centerline will affect the overall yawing moment.

Ideally, you'd like to be able to handle an electric motor bearing failure at an inopportune time in transition without losing control of the aircraft.. Some model hexacopter controllers deliberately gyrate in yaw to hold attitude with a single engine out. This probably wouldn't be a pleasant experience for a pilot onboard so you might need to consider how (or whether) you want to deal with that scenario.

Glad you're building a model first - lots of interesting challenges to work out.

I wouldn't worry too much about addressing Tom's criticism(s). He is oftentimes challenged understanding or conceding any points not made by him - though it certainly appears in this case that he's mistaken the bottom of the airplane (with the nose wheel stalk) for the top in your drawing of the aircraft with the pilot seat in hover orientation.

Andy

And oh by the way 2g, you questioned mr kramers academic credentials, just remember the wrights were'nt college educated, no degrees and they still beat the pants off of Langley, the college golden boy with all the "knowledge" and all the cash. Innovation and smarts are where you find them, sheepskin non mandatory or for that matter even desired. Most of the greatest innovations have come out of garages not universities.

On Sunday, March 20, 2016 at 4:41:42 AM UTC-7, Andy Blackburn wrote:

A second potential issue is how to counteract the torque of the gas motor and prop, which see to be substantially larger than the electric motors and props.

Re-read the Kickstarter description. Offset angle on the electrics should help. Presumably you'll get additional torque when accelerating to transition. You'll need to handle the variation presumably by accelerating the electric motors spinning the opposite direction from he main gas motor. I'm guessing you might need some limits on how much you can accelerate so you don't run out of countering torque.

On Sunday, March 20, 2016 at 1:39:25 AM UTC-4, 2G wrote:
On Saturday, March 19, 2016 at 5:00:26 PM UTC-7, DaleKramer wrote:
And for the record, to my knowledge, I did not says that this was a revolutionary design.

Again, your attitude stinks! I can't fix stupid - you shouldn't be attempting a public venture, it just isn't your style.

You wrote "I believe that this revolution of flight". Case closed.

Wow, I have heard of out of context before but this is still hard to believe!

When I said that and in the same sentence you can tell that I was referring to multirotors in general. In fact the word vLazair or 'my design' in nowhere to be found in that particular post.

This is what I mean when I speak of agenda.

You are correct about something, case closed, I choose to end further response to your posts.

I will respond to the other intelligent and 'non-attacking' posts when I calm down.