Fast helicopters

[George Vranek]

In the last weeks, there is a big silence in this NG regarding fast flying
helicopters. Please have a look at www.vranek.ch/diskrotor.htm and publish
your comments and questions if any in this NG.
Geoge

[Bernie the Bunion]

George Vranek > wrote:

> In the last weeks, there is a big silence in this NG regarding fast flying
> helicopters.

And your point is....?????

> Please have a look at www.vranek.ch/diskrotor.htm and publish
> your comments and questions if any in this NG.

Okay.... It's your personal vanity website with slow loading graphics
and tiny blue type on a gray and black background that's extremely
difficult to read.

That was my comment..... Now my question.

Why is it important that we go and visit your personal vanity
website...???

> Geoge

Bernie

[CoE]

More moving parts costing even more money with more of a chance of falling
to the ground and making more of a mess. The only thing that is not
excessive about that..... thing....... is the amount of insurance companies
willing to insure it.

"George Vranek" > wrote in message
...
> In the last weeks, there is a big silence in this NG regarding fast flying
> helicopters. Please have a look at www.vranek.ch/diskrotor.htm and publish
> your comments and questions if any in this NG.
> Geoge
>
>

[Stevenatherton]

not surprised opened it what was i supposed to sea any one any idea

[[email protected]]

"George Vranek" > wrote:

> helicopters. Please have a look at www.vranek.ch/diskrotor.htm and publish

The diskrotor/diskCopter has been discussed here before. The
conclusion was that it was impractical and probably impossible. When
flying forward, the normal helicopter disk plane has a negative pitch
angle relative to the ground. Putting a huge round airfoil up there
with a negative pitch angle would make you crash and not fly faster.
Not only that, but the disk "airfoil" would not really be a very good
airfoil with the same shape on both ends would it. If you disagree, I
suggest you build a model and fly it faster than 100 mph and see what
happens.

Dennis.


Dennis Hawkins
n4mwd AT amsat DOT org (humans know what to do)

"A RECESSION is when you know somebody who is out of work.
A DEPRESSION is when YOU are out of work.
A RECOVERY is when all the H-1B's are out of work."
To find out what an H-1B is and how they are putting
Americans out of work, visit the following web site
and click on the "Exporting America" CNN news video:
http://zazona.com/ShameH1B/MediaClips.htm

[Dave Jackson]

The late and great aerodynamist ,Wieslaw Z. Stepmewski, believed that the
best answer for faster VTOL aircraft will be a unifying of the 'Intermeshing
Configuration', the 'ABC Principle' and 'Low Tip Speed Philosophy'.
For more info; http://www.UniCopter.com/1093.html

[George Vranek]

When flying forward, the Diskrotor Helicopter disk plane has a positive
pitch angle relative to the ground. The thrust necessary for forward flight
is provided by the jet stream and not by the rotor as a conventional
helicopter does. A model acc.to your proposal has flown stright and level 5
years ago. The disk airfoil has similar abilities as a conventional airfoil
with a partially open split flap, which are surprisingly good. See Ira H.
Abbot: Theory of Wing Sections or similar.

George

> wrote in message
...
> "George Vranek" > wrote:
>
> > helicopters. Please have a look at www.vranek.ch/diskrotor.htm and
publish
>
> The diskrotor/diskCopter has been discussed here before. The
> conclusion was that it was impractical and probably impossible. When
> flying forward, the normal helicopter disk plane has a negative pitch
> angle relative to the ground. Putting a huge round airfoil up there
> with a negative pitch angle would make you crash and not fly faster.
> Not only that, but the disk "airfoil" would not really be a very good
> airfoil with the same shape on both ends would it. If you disagree, I
> suggest you build a model and fly it faster than 100 mph and see what
> happens.
>
> Dennis.
>
>
> Dennis Hawkins
> n4mwd AT amsat DOT org (humans know what to do)
>
> "A RECESSION is when you know somebody who is out of work.
> A DEPRESSION is when YOU are out of work.
> A RECOVERY is when all the H-1B's are out of work."
> To find out what an H-1B is and how they are putting
> Americans out of work, visit the following web site
> and click on the "Exporting America" CNN news video:
> http://zazona.com/ShameH1B/MediaClips.htm
>

[[email protected]]

I still seriously doubt that such a craft would be practical or even
possible. Is there video of this model flying on the net somewhere?

In any case, simply adding wings to the side of a helicopter will
increase its maximum forward speed significantly without the nead for
a heavy disk and complex control systems.

Dennis.

"George Vranek" > wrote:

> When flying forward, the Diskrotor Helicopter disk plane has a positive
> pitch angle relative to the ground. The thrust necessary for forward flight
> is provided by the jet stream and not by the rotor as a conventional
> helicopter does. A model acc.to your proposal has flown stright and level 5
> years ago. The disk airfoil has similar abilities as a conventional airfoil
> with a partially open split flap, which are surprisingly good. See Ira H.
> Abbot: Theory of Wing Sections or similar.
>
> George
>
> > wrote in message
> ...
> > "George Vranek" > wrote:
> >
> > > helicopters. Please have a look at www.vranek.ch/diskrotor.htm and
> publish
> >
> > The diskrotor/diskCopter has been discussed here before. The
> > conclusion was that it was impractical and probably impossible. When
> > flying forward, the normal helicopter disk plane has a negative pitch
> > angle relative to the ground. Putting a huge round airfoil up there
> > with a negative pitch angle would make you crash and not fly faster.
> > Not only that, but the disk "airfoil" would not really be a very good
> > airfoil with the same shape on both ends would it. If you disagree, I
> > suggest you build a model and fly it faster than 100 mph and see what
> > happens.
> >
> > Dennis.
> >
> >
> > Dennis Hawkins
> > n4mwd AT amsat DOT org (humans know what to do)
> >
> > "A RECESSION is when you know somebody who is out of work.
> > A DEPRESSION is when YOU are out of work.
> > A RECOVERY is when all the H-1B's are out of work."
> > To find out what an H-1B is and how they are putting
> > Americans out of work, visit the following web site
> > and click on the "Exporting America" CNN news video:
> > http://zazona.com/ShameH1B/MediaClips.htm
> >
>
>

Dennis Hawkins
n4mwd AT amsat DOT org (humans know what to do)

"A RECESSION is when you know somebody who is out of work.
A DEPRESSION is when YOU are out of work.
A RECOVERY is when all the H-1B's are out of work."
To find out what an H-1B is and how they are putting
Americans out of work, visit the following web site
and click on the "Exporting America" CNN news video:
http://zazona.com/ShameH1B/MediaClips.htm

[George Vranek]

I am sorry, but there is no video of this model. Nearly each helicopter
company has made trials with adding wings to their machines and all dropped
them again. During the hoverig the additional wing acts as a balast only and
reduces the hover efficiency of the machine. The heavy disk is able to store
a lot of kinetic energy, which allows vertical landing in autorotation.

George
> wrote in message
...
>
> I still seriously doubt that such a craft would be practical or even
> possible. Is there video of this model flying on the net somewhere?
>
> In any case, simply adding wings to the side of a helicopter will
> increase its maximum forward speed significantly without the nead for
> a heavy disk and complex control systems.
>
> Dennis.
>
> "George Vranek" > wrote:
>
> > When flying forward, the Diskrotor Helicopter disk plane has a positive
> > pitch angle relative to the ground. The thrust necessary for forward
flight
> > is provided by the jet stream and not by the rotor as a conventional
> > helicopter does. A model acc.to your proposal has flown stright and
level 5
> > years ago. The disk airfoil has similar abilities as a conventional
airfoil
> > with a partially open split flap, which are surprisingly good. See Ira
H.
> > Abbot: Theory of Wing Sections or similar.
> >
> > George
> >
> > > wrote in message
> > ...
> > > "George Vranek" > wrote:
> > >
> > > > helicopters. Please have a look at www.vranek.ch/diskrotor.htm and
> > publish
> > >
> > > The diskrotor/diskCopter has been discussed here before. The
> > > conclusion was that it was impractical and probably impossible. When
> > > flying forward, the normal helicopter disk plane has a negative pitch
> > > angle relative to the ground. Putting a huge round airfoil up there
> > > with a negative pitch angle would make you crash and not fly faster.
> > > Not only that, but the disk "airfoil" would not really be a very good
> > > airfoil with the same shape on both ends would it. If you disagree, I
> > > suggest you build a model and fly it faster than 100 mph and see what
> > > happens.
> > >
> > > Dennis.
> > >
> > >
> > > Dennis Hawkins
> > > n4mwd AT amsat DOT org (humans know what to do)
> > >
> > > "A RECESSION is when you know somebody who is out of work.
> > > A DEPRESSION is when YOU are out of work.
> > > A RECOVERY is when all the H-1B's are out of work."
> > > To find out what an H-1B is and how they are putting
> > > Americans out of work, visit the following web site
> > > and click on the "Exporting America" CNN news video:
> > > http://zazona.com/ShameH1B/MediaClips.htm
> > >
> >
> >
>
> Dennis Hawkins
> n4mwd AT amsat DOT org (humans know what to do)
>
> "A RECESSION is when you know somebody who is out of work.
> A DEPRESSION is when YOU are out of work.
> A RECOVERY is when all the H-1B's are out of work."
> To find out what an H-1B is and how they are putting
> Americans out of work, visit the following web site
> and click on the "Exporting America" CNN news video:
> http://zazona.com/ShameH1B/MediaClips.htm
>

[[email protected]]

Any extra weight, including wings, will act as ballast. The thing is
that if you want a fast helicopter, you have to pay for it somehow.
That big disk on top of your diskcopter is a heck of a huge ballast
too.

The simplest way to make a helicopter go faster is to simply increase
the rotor rpm. That way, the differential of lift as the helicopter
goes faster and faster is less significant than a slower turning
rotor. That is, at 400 mph tip speed and at 100 mph forward velocity,
you have a 200 mph differential or 50% of the tip speed. At 1000 mph
tip speed, you still have a 200 mph differential speed but its only
20% of the tip speed.

So in this example, a helicopter with a 1000 mph tip speed could go
forward at 250 mph before hitting 50% differential.

I'm not sure what the actual tip speed is, but I know that a lot of
modern fully articulated systems run at tip speeds just under the
speed of sound in order to significantly reduce the chances of ground
resonance.

Dennis.

"George Vranek" > wrote:

> I am sorry, but there is no video of this model. Nearly each helicopter
> company has made trials with adding wings to their machines and all dropped
> them again. During the hoverig the additional wing acts as a balast only and
> reduces the hover efficiency of the machine. The heavy disk is able to store
> a lot of kinetic energy, which allows vertical landing in autorotation.

Dennis Hawkins
n4mwd AT amsat DOT org (humans know what to do)

"A RECESSION is when you know somebody who is out of work.
A DEPRESSION is when YOU are out of work.
A RECOVERY is when all the H-1B's are out of work."
To find out what an H-1B is and how they are putting
Americans out of work, visit the following web site
and click on the "Exporting America" CNN news video:
http://zazona.com/ShameH1B/MediaClips.htm

[Stan Gosnell]

wrote in
:

> I'm not sure what the actual tip speed is, but I know that a lot of
> modern fully articulated systems run at tip speeds just under the
> speed of sound in order to significantly reduce the chances of ground
> resonance.

Do you mean at a hover? I don't think that's the case. If the tip speed
is just below supersonic at a hover, then at a very low forward airspeed
they'd go supersonic, & all kinds of bad things would happen, not the least
being huge amounts of noise, which is already the bane of helicopters.
Rotors have to be far below supersonic at a hover so the leading blade
doesn't go supersonic in fast cruise. Even the UH1 blades can approach
supersonic near Vne, and the tailrotor blades are close all the time.

--
Regards,

Stan

[mm]

> wrote in message
...
>
> The simplest way to make a helicopter go faster is to simply increase
> the rotor rpm. That way, the differential of lift as the helicopter
> goes faster and faster is less significant than a slower turning
> rotor. That is, at 400 mph tip speed and at 100 mph forward velocity,
> you have a 200 mph differential or 50% of the tip speed. At 1000 mph
> tip speed, you still have a 200 mph differential speed but its only
> 20% of the tip speed.
>
> So in this example, a helicopter with a 1000 mph tip speed could go
> forward at 250 mph before hitting 50% differential.
>
> I'm not sure what the actual tip speed is, but I know that a lot of
> modern fully articulated systems run at tip speeds just under the
> speed of sound in order to significantly reduce the chances of ground
> resonance.
>
> Dennis.
>
Real helicopters use a tip speed on the order of 700-800 ft/sec (475-545
mph), well below the speed of sound. This has nothing to do with ground
resonance. It is driven by blade loads, vibration & stability, and noise at
high speeds.

[[email protected]]

The fully articulated hub design is susceptable to ground resonance
when landing. By increasing the rotor speed to just under the speed
of sound, that is, so nothing goes faster than the speed of sound even
at max forward velocity, the risk of ground resonance when landing is
significantly reduced. There are other advantages to speeding up a
fully articulated hub, but not flying apart when you land is a big
one.

Dennis.


"mm" > wrote:

> Real helicopters use a tip speed on the order of 700-800 ft/sec (475-545
> mph), well below the speed of sound. This has nothing to do with ground
> resonance. It is driven by blade loads, vibration & stability, and noise at
> high speeds.
>
>

Dennis Hawkins
n4mwd AT amsat DOT org (humans know what to do)

"A RECESSION is when you know somebody who is out of work.
A DEPRESSION is when YOU are out of work.
A RECOVERY is when all the H-1B's are out of work."
To find out what an H-1B is and how they are putting
Americans out of work, visit the following web site
and click on the "Exporting America" CNN news video:
http://zazona.com/ShameH1B/MediaClips.htm

[mm]

> wrote in message
...
>
> The fully articulated hub design is susceptable to ground resonance
> when landing. By increasing the rotor speed to just under the speed
> of sound, that is, so nothing goes faster than the speed of sound even
> at max forward velocity, the risk of ground resonance when landing is
> significantly reduced. There are other advantages to speeding up a
> fully articulated hub, but not flying apart when you land is a big
> one.
>
> Dennis.
You clearly don't know anything about ground resonance. It has little or
nothing to do with the blade tip Mach number.

[[email protected]]

"mm" > wrote:

> You clearly don't know anything about ground resonance. It has little or
> nothing to do with the blade tip Mach number.

I don't pretend to be a fully articulated hub expert, but this is not
something I made up. It comes from an FAA inspector who makes his
living flying all sorts of helicopters. He IS an expert. Are YOU an
FAA inspector? Are you qualified to say that he is mistaken?

Think about the word "resonance". Do resonance and frequency go hand
in hand? By increasing the rotor RPM, do you increase the frequency
of rotation? Of course you do, its the same thing. If you sing a
perfect pitch into a tuning fork, does it also vibrate at resonance?
Yes. If you sing at a non-resonant frequency, does it still vibrate?
No. Are marching soldiers told to break step when crossing a bridge?
Yes. Why? Resonance. Think about this and what ground resonance
actually is.

Before you say this guy doesn't know anything about what he does for a
living, I suggest that you think about it a little while.

Dennis.



Dennis Hawkins
n4mwd AT amsat DOT org (humans know what to do)

"A RECESSION is when you know somebody who is out of work.
A DEPRESSION is when YOU are out of work.
A RECOVERY is when all the H-1B's are out of work."
To find out what an H-1B is and how they are putting
Americans out of work, visit the following web site
and click on the "Exporting America" CNN news video:
http://zazona.com/ShameH1B/MediaClips.htm

[mm]

> wrote in message
...
> "mm" > wrote:
>
> > You clearly don't know anything about ground resonance. It has little
or
> > nothing to do with the blade tip Mach number.
>
> I don't pretend to be a fully articulated hub expert, but this is not
> something I made up. It comes from an FAA inspector who makes his
> living flying all sorts of helicopters. He IS an expert. Are YOU an
> FAA inspector? Are you qualified to say that he is mistaken?
>
> Think about the word "resonance". Do resonance and frequency go hand
> in hand? By increasing the rotor RPM, do you increase the frequency
> of rotation? Of course you do, its the same thing. If you sing a
> perfect pitch into a tuning fork, does it also vibrate at resonance?
> Yes. If you sing at a non-resonant frequency, does it still vibrate?
> No. Are marching soldiers told to break step when crossing a bridge?
> Yes. Why? Resonance. Think about this and what ground resonance
> actually is.
>
> Before you say this guy doesn't know anything about what he does for a
> living, I suggest that you think about it a little while.
>
> Dennis.
>
Yes, as a matter of fact I am qualified to say he is mistaken. I can
guarantee you that I know MUCH more about ground resonance than you or your
source. I challenge you to find a single reputable reference (text book,
technical paper, certification documentation, FAA training material, etc.)
that relates ground resonance directly to tip Mach number. Your source may
be the worlds ultimate helicopter pilot, but I don't think that this is much
of credential with respect to rotor aeromechanics and structural dynamics.

The original analysis of helicopter ground resonance was by Coleman and
Fiengold, NACA TN 3844. Read it, and will not find any mention of tip Mach
number.

Your tuning fork and marching soldiers examples are essentially meaningless
in this context.

[[email protected]]

I never said anything about tip mach number. I said "rotor speed".
The two are similar, but not the same. I'm not going to sit here and
argue with an anonymous person who thinks a "diskCopter" is practical.
Your facts about ground resonance may have been accurate 50 years ago,
but they are out of date.

Dennis.


"mm" > wrote:


> Yes, as a matter of fact I am qualified to say he is mistaken. I can
> guarantee you that I know MUCH more about ground resonance than you or your
> source. I challenge you to find a single reputable reference (text book,
> technical paper, certification documentation, FAA training material, etc.)
> that relates ground resonance directly to tip Mach number. Your source may
> be the worlds ultimate helicopter pilot, but I don't think that this is much
> of credential with respect to rotor aeromechanics and structural dynamics.
>
> The original analysis of helicopter ground resonance was by Coleman and
> Fiengold, NACA TN 3844. Read it, and will not find any mention of tip Mach
> number.
>
> Your tuning fork and marching soldiers examples are essentially meaningless
> in this context.
>
>
>
>

Dennis Hawkins
n4mwd AT amsat DOT org (humans know what to do)

"A RECESSION is when you know somebody who is out of work.
A DEPRESSION is when YOU are out of work.
A RECOVERY is when all the H-1B's are out of work."
To find out what an H-1B is and how they are putting
Americans out of work, visit the following web site
and click on the "Exporting America" CNN news video:
http://zazona.com/ShameH1B/MediaClips.htm

[mm]

> wrote in message
...
>
> I never said anything about tip mach number. I said "rotor speed".
> The two are similar, but not the same.

Your original quote was "By increasing the rotor speed to just under the
speed
of sound,..." . When you talk about "rotor speed" and the "speed of sound"
in the same sentence, blade tip Mach number is the only rational way to
connect these two. How else can anyone compare "rotor speed" with the
"speed of sound", please tell us. Without my connecting these two
quantities this way for you, everything you said is completely meaningless
(as opposed to simply wrong).

>I'm not going to sit here and
> argue with an anonymous person who thinks a "diskCopter" is practical.

I've NEVER said anything about the "diskCopter" at all in this discusssion.
(For the record I think the "diskCopter" is silly.)

> Your facts about ground resonance may have been accurate 50 years ago,
> but they are out of date.
>

We're talking about physics here, what part of that "went out of date".
Please tell us what part of the analysis "no longer applies". I'll bet you
don't even really know what ground resonance is. How about this, tell the
group just what is in resonance with what. What is the frequency of the
blade motions, what is the frequency of the body motions? How is it
prevented? Do you know the FAA or military requirements with respect to
ground resonance? Tell us how many helicopters you have done a real
stability analysis for. When you can do this, then please explain further
your comments about the "speed of sound" and it's crucial role in this
phenomenom, I'd really like to hear your detailed analysis.

I really don't care about what you know and don't know, I just get a little
annoyed with people on the internet who spout complete nonsense to the rest
of the world, and then rather than trying to learn something argue with
reality. You might mislead someone with your nonsense and cause some harm
some day. I'm sorry if tone of this conversation is less than polite, I
just don't deal well with nonsense.

[Bart]

I don't mean to further yet another moronic discussion about yet
another pie in the sky (lol) rotorcraft, but MM, regardless of
who he is, is correct. Ground resonance has nothing to do with
rotor tip speed. Its mainly germane to helicopters which have
shock-struts as the main rotor rotational rate crosses the
resonant frequency(ies) of the struts. It tends to be exaggerated
and more dangerous in machines with four struts and three blades.
Nothing has ever caused my Jetranger to enter the onset of
ground resonance. Know why?; Two blades, No struts....Hmmm.

Mach number my eye, and who the heck cares about ground resonance
in a discussion on increasing Vmax?

Bart

wrote:
> I never said anything about tip mach number. I said "rotor speed".
> The two are similar, but not the same. I'm not going to sit here and
> argue with an anonymous person who thinks a "diskCopter" is practical.
> Your facts about ground resonance may have been accurate 50 years ago,
> but they are out of date.
>
> Dennis.
>

[[email protected]]

Like I said, my source does know what he is talking about and you
don't. I am not the expert and I cannot adequately explain why the
rotor speed is important for preventing ground resonance. However, my
source told me that it is and he is far more credible than you. How
many of the newer fully articulated hubs have tip speeds of only 400
mph? I wonder why they sped things up.

The other poster did have a point regarding landing struts. Fixed
struts hitting the ground are high(er) frequency. Spring loaded
struts are low frequency. Its the frequency imparted into the body
and thus the blades during impact, not just the impact itself. Past
that, I'm not going to say any more.

I suppose in your next post that you will be spouting nonsense about
how it has something to do with gravity and the space-time contuinuum
or something.

Quite frankly, you are a troll. I am not going to waste any more time
with you. If you want to post that you are the helicopter god of the
world, be my guest. I won't challenge you. You are still posting
anonymously and expect us to believe that you are an expert. Get
real.



Dennis.




"mm" > wrote:

<Nonsense deleted>

Dennis Hawkins
n4mwd AT amsat DOT org (humans know what to do)

"A RECESSION is when you know somebody who is out of work.
A DEPRESSION is when YOU are out of work.
A RECOVERY is when all the H-1B's are out of work."
To find out what an H-1B is and how they are putting
Americans out of work, visit the following web site
and click on the "Exporting America" CNN news video:
http://zazona.com/ShameH1B/MediaClips.htm

[mm]

"Bart" > wrote in message
...
> I don't mean to further yet another moronic discussion about yet
> another pie in the sky (lol) rotorcraft, but MM, regardless of
> who he is, is correct. Ground resonance has nothing to do with
> rotor tip speed. Its mainly germane to helicopters which have
> shock-struts as the main rotor rotational rate crosses the
> resonant frequency(ies) of the struts. It tends to be exaggerated
> and more dangerous in machines with four struts and three blades.
> Nothing has ever caused my Jetranger to enter the onset of
> ground resonance. Know why?; Two blades, No struts....Hmmm.
>
> Mach number my eye, and who the heck cares about ground resonance
> in a discussion on increasing Vmax?
>
> Bart
>
What a nice change, someone who does actually understands something about
the issue!

The reason that a JetRanger can not have ground resonance is that it does
not have lag hinges or other source of flexibility in-plane. If the rotor's
natural lag frequency is higher than the rotor speed, as is the case with
the Bell teetering rotors, it is impossible for it to have a ground
resonance instability. Rotors with this characteristic are called
"stiff-inplane". You can have a stiff-inplane rotor with more than 2 blades
(BO105, BK117) and they too are immune from ground resonance. (If look at a
BO105 or BK117 hub you will not see any lag dampers.)

The struts are associated with ground resonance, but not in the way that you
seem to think. They do not cause the problem; they are there to provide the
damping needed to stabilize the system.

If anyone is interested, we could have a nice little productive thread on
ground resonance. If you do care about this subject, though, please, ignore
that guy "Dennis". He really, really doesn't know what he is talking about
on this subject.

[Bernie the Bunion]

> mm > wrote:


> If anyone is interested, we could have a nice little productive thread on
> ground resonance.

Pardon me for sounding snide but if your next nice little productive
thread is like your last one then two other people will participate
besides youself and one of those will be Dennis who you claim
doesn't know what he's talking about.

Sounds like a barn burner to me.

> If you do care about this subject, though, please, ignore
> that guy "Dennis". He really, really doesn't know what he is talking about
> on this subject.

AND YOU DO......!!!!!!!!!!!!!

Your not related to Badwater Bill are you...???????????

[John Roncallo]

George Vranek wrote:
> In the last weeks, there is a big silence in this NG regarding fast flying
> helicopters. Please have a look at www.vranek.ch/diskrotor.htm and publish
> your comments and questions if any in this NG.
> Geoge
>
>


I see a lot of negativity in this NG about this concept but I feel it
has at laest as much merit as a tilt rotor.

J. Roncallo

My opinions posted on this news group are my own and do not represent
the company I work for.

[brien]

I agree the concept has at least as much merit as a tilt rotor.
Brien
"John Roncallo" > wrote in message
...
> George Vranek wrote:
> > In the last weeks, there is a big silence in this NG regarding fast
flying
> > helicopters. Please have a look at www.vranek.ch/diskrotor.htm and
publish
> > your comments and questions if any in this NG.
> > Geoge
> I see a lot of negativity in this NG about this concept but I feel it
> has at laest as much merit as a tilt rotor.
>
> J. Roncallo
>
> My opinions posted on this news group are my own and do not represent
> the company I work for.
>

[George Vranek]

Hallo John, hallo Brien,

thanks for your comparison of the diskrotor with the tiltrotor. But despite
of nearly 50 years long development, the tiltrotor has two faults: It has
not optimal rotors for hovering and not optimal props for cruising. It
means, that a tiltrotor lifts less load in hovering than a conventional
helicopter and cruise slower than a conventional turboprop airplane with
equal installed power.
The diskrotor is optimal for hovering because the big disk brings law and
order in the aerodynamic of a helicopter rotor and the disk with retracted
rotor blades is well suitable for a really fast cruising. Even supersonic
speeds are feasible!!!

George

"brien" > wrote in message
...
> I agree the concept has at least as much merit as a tilt rotor.
> Brien
> "John Roncallo" > wrote in message
> ...
> > George Vranek wrote:
> > > In the last weeks, there is a big silence in this NG regarding fast
> flying
> > > helicopters. Please have a look at www.vranek.ch/diskrotor.htm and
> publish
> > > your comments and questions if any in this NG.
> > > Geoge
> > I see a lot of negativity in this NG about this concept but I feel it
> > has at laest as much merit as a tilt rotor.
> >
> > J. Roncallo
> >
> > My opinions posted on this news group are my own and do not represent
> > the company I work for.
> >
>
>

[John Roncallo]

George Vranek wrote:

> Hallo John, hallo Brien,
>
> thanks for your comparison of the diskrotor with the tiltrotor. But despite
> of nearly 50 years long development, the tiltrotor has two faults: It has
> not optimal rotors for hovering and not optimal props for cruising. It
> means, that a tiltrotor lifts less load in hovering than a conventional
> helicopter and cruise slower than a conventional turboprop airplane with
> equal installed power.
> The diskrotor is optimal for hovering because the big disk brings law and
> order in the aerodynamic of a helicopter rotor and the disk with retracted
> rotor blades is well suitable for a really fast cruising. Even supersonic
> speeds are feasible!!!
>
> George
>
> "brien" > wrote in message
> ...
>


I said the concept has at least as much merit as a tilt rotor. I did not
say better or worse. I fully understand the tilt rotors limitations and
some of the disk rotors.

You are still yet to discover the how practical or impractical your
concept is, and who knows maybe it will just be the most practical
concept since the tail rotor. Maybe you will only need 30 years instead
of 50. If you got the funding go for it. Also if you get the funding let
me know.

John Roncallo

[George Vranek]

"John Roncallo" > wrote in message
om...
> George Vranek wrote:
>
> > Hallo John, hallo Brien,
> >
> > thanks for your comparison of the diskrotor with the tiltrotor. But
despite
> > of nearly 50 years long development, the tiltrotor has two faults: It
has
> > not optimal rotors for hovering and not optimal props for cruising. It
> > means, that a tiltrotor lifts less load in hovering than a conventional
> > helicopter and cruise slower than a conventional turboprop airplane with
> > equal installed power.
> > The diskrotor is optimal for hovering because the big disk brings law
and
> > order in the aerodynamic of a helicopter rotor and the disk with
retracted
> > rotor blades is well suitable for a really fast cruising. Even
supersonic
> > speeds are feasible!!!
> >
> > George
> >
> > "brien" > wrote in message
> > ...
> >
>
>
> I said the concept has at least as much merit as a tilt rotor. I did not
> say better or worse. I fully understand the tilt rotors limitations and
> some of the disk rotors.
>
> You are still yet to discover the how practical or impractical your
> concept is, and who knows maybe it will just be the most practical
> concept since the tail rotor. Maybe you will only need 30 years instead
> of 50. If you got the funding go for it. Also if you get the funding let
> me know.
>
> John Roncallo

Hallo John,

You are right, the most impractical on the diskrotor concept is to get the
funding for it. I have made the first drawing of the diskrotor helicopter in
June 1993 and from that time I have contacted nearly all helicopter makers
(Agusta, Eurocopter, Piasecki, Sikorsky, Westland.........) without any
succes. But I am still optimistic, because the time is ripe for a fast
flying helicopter: There is a certain number of rich people , who are able
to pay 30 millions of US $ for a machine which brings them from New York to
Acapulco without waiting for a slot before take off and without waiting in a
holding pattern before landing. You know, the time is money. If there is a
demand, the suppliers will discover it soon.

George

[Gig Giacona]

"George Vranek" > wrote in message
...
>
> "John Roncallo" > wrote in message
> om...
> > George Vranek wrote:
> >
> > > Hallo John, hallo Brien,
> > >
> > > thanks for your comparison of the diskrotor with the tiltrotor. But
> despite
> > > of nearly 50 years long development, the tiltrotor has two faults: It
> has
> > > not optimal rotors for hovering and not optimal props for cruising. It
> > > means, that a tiltrotor lifts less load in hovering than a
conventional
> > > helicopter and cruise slower than a conventional turboprop airplane
with
> > > equal installed power.
> > > The diskrotor is optimal for hovering because the big disk brings law
> and
> > > order in the aerodynamic of a helicopter rotor and the disk with
> retracted
> > > rotor blades is well suitable for a really fast cruising. Even
> supersonic
> > > speeds are feasible!!!
> > >
> > > George
> > >
> > > "brien" > wrote in message
> > > ...
> > >
> >
> >
> > I said the concept has at least as much merit as a tilt rotor. I did not
> > say better or worse. I fully understand the tilt rotors limitations and
> > some of the disk rotors.
> >
> > You are still yet to discover the how practical or impractical your
> > concept is, and who knows maybe it will just be the most practical
> > concept since the tail rotor. Maybe you will only need 30 years instead
> > of 50. If you got the funding go for it. Also if you get the funding let
> > me know.
> >
> > John Roncallo
>
> Hallo John,
>
> You are right, the most impractical on the diskrotor concept is to get the
> funding for it. I have made the first drawing of the diskrotor helicopter
in
> June 1993 and from that time I have contacted nearly all helicopter makers
> (Agusta, Eurocopter, Piasecki, Sikorsky, Westland.........) without any
> succes. But I am still optimistic, because the time is ripe for a fast
> flying helicopter: There is a certain number of rich people , who are able
> to pay 30 millions of US $ for a machine which brings them from New York
to
> Acapulco without waiting for a slot before take off and without waiting in
a
> holding pattern before landing. You know, the time is money. If there is a
> demand, the suppliers will discover it soon.
>
> George
>
>

I hate to say it but now really isn't the time. The same people that buy
Biz-Jets would be the market ant that market is in the tank.

Also, NOONE would want a fast helicopter more than the military and if any
of the companies above thought the system was viable they would have bought
it or at least optioned it.

[John Roncallo]

George Vranek wrote:

>
> You are right, the most impractical on the diskrotor concept is to get the
> funding for it. I have made the first drawing of the diskrotor helicopter in
> June 1993 and from that time I have contacted nearly all helicopter makers
> (Agusta, Eurocopter, Piasecki, Sikorsky, Westland.........) without any
> succes. But I am still optimistic, because the time is ripe for a fast
> flying helicopter: There is a certain number of rich people , who are able
> to pay 30 millions of US $ for a machine which brings them from New York to
> Acapulco without waiting for a slot before take off and without waiting in a
> holding pattern before landing. You know, the time is money. If there is a
> demand, the suppliers will discover it soon.
>
> George
>

It is not that it is a diskrotor concept or something new that makes
funding a challange. Funding is always a challenge, I'v seen much more
bizzare ideas get the funding.

All those companys wont be interested unless some government branch like
NASA or DARPA ask's them to research it and pays them to do so. I
suggest you submit the idea as an DOD or NASA SBIR. Visit
http://www.acq.osd.mil/sadbu/sbir/othersites/index.htm. I belive Carter
Copter got started from a NASA SBIR.

My opinions experessed here are my own and do not represent the company
I work for.

John Roncallo

[Bart]

George,

I don't know why you're bothering to blather on about the concept here.
Nobody is going to invest in the concept unless its proven viable. Make
a model and fly it. Thats what most of the chopper inventors did to
prove their ideas.

You also need to revise your ideas about how your example customer
travels. They dont generally need a slot because theyre not parking
their planes at high congestion Class B airports. Since your concept
will never fly at M.77+, it would never be competitive in the 2500nm
range class of aircraft.

Bart


> Hallo John,
>
> You are right, the most impractical on the diskrotor concept is to get the
> funding for it. I have made the first drawing of the diskrotor helicopter in
> June 1993 and from that time I have contacted nearly all helicopter makers
> (Agusta, Eurocopter, Piasecki, Sikorsky, Westland.........) without any
> succes. But I am still optimistic, because the time is ripe for a fast
> flying helicopter: There is a certain number of rich people , who are able
> to pay 30 millions of US $ for a machine which brings them from New York to
> Acapulco without waiting for a slot before take off and without waiting in a
> holding pattern before landing. You know, the time is money. If there is a
> demand, the suppliers will discover it soon.
>
> George
>
>

[George Vranek]

"Gig Giacona" > wrote in message
...
>
> I hate to say it but now really isn't the time. The same people that buy
> Biz-Jets would be the market ant that market is in the tank.
>
> Also, NOONE would want a fast helicopter more than the military and if any
> of the companies above thought the system was viable they would have
bought
> it or at least optioned it.
>
Hallo Gig,

The Biz-Jets market is in the tank due to the problems with getting
permition for take-of and landing on heavy crowded airports. Due to the high
population density in Europe are such problems here much worse than in your
country. You happy Americans! You have still enough place where to live and
even where to fly. The diskrotor helicopter is able to take off and land on
each heliport and cruise from point A to B with a speed limited only by
installed power. Also, EVERYBODY would want a fast helicopter.

George

[George Vranek]

"John Roncallo" > wrote in message
om...
>
> It is not that it is a diskrotor concept or something new that makes
> funding a challange. Funding is always a challenge, I'v seen much more
> bizzare ideas get the funding.
>
> All those companys wont be interested unless some government branch like
> NASA or DARPA ask's them to research it and pays them to do so. I
> suggest you submit the idea as an DOD or NASA SBIR. Visit
> http://www.acq.osd.mil/sadbu/sbir/othersites/index.htm. I belive Carter
> Copter got started from a NASA SBIR.
>
> My opinions experessed here are my own and do not represent the company
> I work for.
>
> John Roncallo
>
Hallo John,

Thanks for your info regarding NASA and DARPA. Tthey support preferably
companies, but I am a retired aeronautical engineer and hobby flyer.
Therefore I would prefer to work as a consultant for a company developing
the diskrotor helicopter with the NASA or DARPA support.
According to EAA e-HOT LINE, Vol.3, No.53, the Carter Company received now a
quarter-million Dollar DARPA contract. In January 1997 I have sent to Mr.
Jay Carter a sketch of his Gyrocopter equipped with a disk rotor, but I
receved no answer from him.

George

[John Roncallo]

George Vranek wrote:

> "John Roncallo" > wrote in message
> om...
>
>>It is not that it is a diskrotor concept or something new that makes
>>funding a challange. Funding is always a challenge, I'v seen much more
>>bizzare ideas get the funding.
>>
>>All those companys wont be interested unless some government branch like
>>NASA or DARPA ask's them to research it and pays them to do so. I
>>suggest you submit the idea as an DOD or NASA SBIR. Visit
>>http://www.acq.osd.mil/sadbu/sbir/othersites/index.htm. I belive Carter
>>Copter got started from a NASA SBIR.
>>
>>My opinions experessed here are my own and do not represent the company
>>I work for.
>>
>>John Roncallo
>>
>
> Hallo John,
>
> Thanks for your info regarding NASA and DARPA. Tthey support preferably
> companies, but I am a retired aeronautical engineer and hobby flyer.
> Therefore I would prefer to work as a consultant for a company developing
> the diskrotor helicopter with the NASA or DARPA support.
> According to EAA e-HOT LINE, Vol.3, No.53, the Carter Company received now a
> quarter-million Dollar DARPA contract. In January 1997 I have sent to Mr.
> Jay Carter a sketch of his Gyrocopter equipped with a disk rotor, but I
> receved no answer from him.
>
> George
>
>

The SBIR programs are very specifically for small businesses and
individuals. The initial phase SBIR program will give you seed money, I
belive up to $30,000 and one year, to help you research and develope
your ideas. If what you develope is promising you may get further awards
which if I recall are up to $600,000 to further develope the concept.
Somewhere along the line if the agency sponsoring the project likes the
idea they may ask a major helicopter company to get involved or just
fund you further. This is the way to start.

You say you want to work as a consultant. Unless you have already
developed a full scale disk rotor helicopter or a very significanr
model, no one will be likely to take you on as a consultant because at
this point you have what may be a reasonable concept but not
significantly more knowledge than others in the industry at applying the
concept.

At this point you have come up with a concept. Tell me just how far you
have gone with it.

1) Have you done weight trade studys, What will the disk weigh, What
will the retraction mechanism weigh. How much compromise will you accept
on hover performance due to these weight penalties.

2) How do you plan to motor the rotor in auto rotation with no blade in
what would normally be the motoring region of the blade.

3) You had made some negative comments on fixed wings for helicopters,
however have you considered them on your disk rotor. I think fixed wings
would only be an asset on this aircraft since the wings would be under
the no lift producing portion of the rotor.

There is nothing I see impossible here. Only significant reaserch is
needed to prove or disprove the concepts viability. Companies are
sometimes not too eager to spend money on these concepts because what at
first appears to be significant breakthroughs in technology often wither
and die or just come up short of expectations and end up usefull but not
cost effective.

I may start a flame war but I belive the V-22 is in this mode right now.
Yes it works, but it has H-53E power and H-60 payload and God knows what
for aquisition and maintenance costs. You have to ask was this worth it.
Your disk rotor will only have similare compromises, maybe not as bad,
maybe worse.

My opinions experessed here are my own and do not represent the company
I work for.

John Roncallo