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A400M Rollout

Haletown:

Government Motors in action
http://dustmybroom.com/index.php?option=com_content&view=article&id=11848:government-motors-in-action&catid=45:-nanny-bastards

Not quite on, er, topic but related.

Mark
Ottawa
 
It looks like it has made more flights and covered more territory as "pieces" than it has as an aircraft. 

http://www.youtube.com/watch?v=EQ5E0kfnY5I&feature=related



;D
 
In the event, any A400Ms we might have acquired would have been in service well after  (as things now stand)  the end of the CF's Afghan mission.

Great timing or what?

Mark
Ottawa
 
All of that carbon fibre...

The greenies are going to be really impressed when the first one crashes and burns.
 
Loachman said:
All of that carbon fibre...

The greenies are going to be really impressed when the first one crashes and burns.

- Yup. Wear a mask if you're downwind - and put a mask on your computers, too!
 
I first heard of this thing in 2003. Glad I wasn't waiting for it anxiously!
 
And Airbus had the temerity to say they were going to sue Canada for damages because the government went with the C-130 vice the A400M.
Whiny Europeans!! >:D
 
Those scimitar blades seem to be the Latest Word. Wonder why they don't use them on helicopters?
 
Because helicopters do not have propellers.
 
Ah, but helicopters DO have rotors.

And, of course, not ALL helicopters are without propellers.

http://en.wikipedia.org/wiki/AH-56_Cheyenne

Delaying the onset of shock wave formation at the rotor tips might be useful in increasing the top speed of helicoptors, might it not? Because helicopters are usually limited to about 250 mph speeds.

The Osprey has a 315 mph top speed, because it can change its power-to-air interface devices' axis from vertical to horizontal. Perhaps scimitar-shaped blades would raise that top speed even further, because the blades are rather long.
 
The V-22 does have considerably more powerful engines that can drive the props.
I'm no aeronautical engineer but i do know that the more surface area of a blade, the more energy is going to be required.
I'll defer to Loachman iRT this.

I think the A-400M is going to have a lot of growing pains, if it even gets to production.
 
Ah, but helicopters DO have rotors.

And, of course, not ALL helicopters are without propellers.

oh boy.  Where is that face-palming smiley when you need it?

You do realize that Loachman flies helicopters for a living... and has for a real, real long time?  To presume to tell him what the various "bits" DO might be construed as  a bit... presumptuous, no?
 
sm1lodon said:
Ah, but helicopters DO have rotors.

So I've noticed.

They're still not propellers. They are wings, and combine the functions of wings, elevators, ailerons, and propellers. The aerodynamics are a little different from, and much more complex than, independent wings and control surfaces and propellers.

sm1lodon said:
And, of course, not ALL helicopters are without propellers.

http://en.wikipedia.org/wiki/AH-56_Cheyenne

And there are exactly how many of those flying around?

sm1lodon said:
Delaying the onset of shock wave formation at the rotor tips might be useful in increasing the top speed of helicoptors, might it not?

I doubt it. I'm not a helicopter scientist, but I've never heard of that as a factor. Blade tips do not move that fast, nor do they need to.

Well, perhaps, according to the refs in the following post. I've never had any interest in flying at such speeds. It's much harder to dodge cows.

sm1lodon said:
Because helicopters are usually limited to about 250 mph speeds.

Look up "retreating blade stall".

In any case, I see no reason for helicopters to fly that fast in a typical military environment. Typical speeds in a conventional tactical environment are 100 knots tops, and often much slower. High speeds are not required for the short distances usually involved, and reduce agility and reaction time available. Osprey was designed and built for a specific purpose, and not to replace battlefield helicopters. It is entirely unsuitable for that.

sm1lodon said:
The Osprey has a 315 mph top speed, because it can change its power-to-air interface devices' axis from vertical to horizontal. Perhaps scimitar-shaped blades would raise that top speed even further, because the blades are rather long.

Perhaps that is not a suitable design in non-propeller-mode.

In any case, that's completely irrelevant for our purposes.
 
Far from the thread subject but since someone brought up rotor blades and speed :

http://en.wikipedia.org/wiki/BERP_rotor
http://terpconnect.umd.edu/~leishman/Aero/berp.html
 
CDN Aviator said:
Far from the thread subject but since someone brought up rotor blades and speed :
en.wikipedia.org/wiki/BERP_rotor

...such as the Westland Super Lynx, which holds the helo speed record of just over 400km/hr
Royal_Navy_Lynx_318.jpg
 
...yeah, but that spinny thing on the back LOOKS like a propeller, no?
 
SeaKingTacco said:
oh boy.  Where is that face-palming smiley when you need it?

You do realize that Loachman flies helicopters for a living... and has for a real, real long time?  To presume to tell him what the various "bits" DO might be construed as  a bit... presumptuous, no?

I wasn't telling anyone what various bits do. I was affirming that though most helicopters DON'T have propellers, they DO have rotors.

Another reason I figure a scimitar-shaped ROTOR blade might be useful is that if you could create a blade that was capable of being rotated more quickly without the onset of any unwanted transonic behaviors on its way forward, it might be rotating quickly enough that as it went backwards, it would provide sufficient lift at higher airframe speeds to increase the top speed of the helicopter.

I am aware that as velocity in any horizontal vector increases, the effectiveness of the rotor blades being able to create lift as they are on the backwards part of their rotation relative to airflow decreases.

I doubt that it is likely that any kind of rotor blade could be come up with that would allow much higher RPM/average blade speed relative to the airflow as it travels backwards to dramatically impact top speed. But I do not know, and I've never seen anything that indicates anyone has tried that sort of thing.

I've even thought of rotors that have a much larger base than tip so that as the rotor blade is on its way back, the inner portion (nearest the vertical axis) not having enough speed to overcome relative airspeed might not be such a handicap because the air flowing backwards over it would generate some lift. Of course, this could potentially contribute to it producing too much lift going forward, but, being closer to the center of the axis of the rotor, it would not experience a dramatic difference in relative airspeed like the rotor tips do.

I have also considered rotor blades that have a very low-profile supersonic wing design profile so they would provide lift even at transonic speeds relative to the airflow at the outer portions of the blades, while the inner portions of the blades would be designed for subsonic lift.

Someone on here posted that helicopters don't spend much of their time far above 100 mph or so, so it is likely no one really CARES about making a chopper go over 250mph, because that is far outside its operational usefulness envelope, like making a fighter plane able to do mach 5.

But, some ideas I just like to explore because it might have some merit, someday. Everything that is science today was at one time science fiction and someone's (often ridiculed) flight of fancy.

Having an assault rifle that doubles as an espresso maker might be possible, but, WHY? Having a chopper that can actually do 400 mph may even be possible with existing technology, but as our esteemed learned fellow-forum-member on here pointed out, what would be the point?

I don't explore far-out ideas to be controversial or start arguments. I try not to be sarcastic and self-congralutorily witty. I mention stuff because I actually HAVE thought about "why not do it this way?" and can learn from others. Sometimes I offer a summary of what I have learned so anyone who feels so inclined can add whatever they want to it or refute it outright.

Now, to the experienced soldier/pilot/sailor this stuff might look just ridiculously obvious, but, that is why the search function exists, to find the ridiculously obvious, if it already exists here.

And often, just because something is possible, doesn't mean that it would offer any significant improvement over the existing technology, especially when costs of replacing the existing technology so far overshadow the 1% improvement that might available by the new thing.
 
sdpauoiuapdsf said:
Someone on here posted that helicopters don't spend much of their time far above 100 mph or so, so it is likely no one really CARES about making a chopper go over 250mph, because that is far outside its operational usefulness envelope, like making a fighter plane able to do mach 5.

First, I know nothing of fling-wing aerodynamics, but where my thoughts went with the whole rotor shape change was to allow faster rotor speeds to increase the max GWT of a machine.  I don't know if if works this way or not, if increased rotor speed allows for greater lift capability.  I gotta go with the thought that if this was beneficial, someone would have incorporated it by now.

I do disagree with the above quote though for in theater ops.  Helo speed can be highly beneficial depending on the employment of the asset.  As an air defense platform (aka: attack helo), speed can be highly beneficial.  A properly armed attack helo capable of speeds between 250 and 300 KIAS at various altitudes are very effective at providing low level harassment of tactical transport ops as well as providing the same ops with useful and beneficial attack coverage.  This is a capability Canada doesn't have, but would be beneficial (although probably not cost effective for what we do).  Apparently there's some issue with escort roles for our Griffon v. the Chinook due to speed.
 
hauger said:
Apparently there's some issue with escort roles for our Griffon every escort aircraft v. the Chinook due to speed.

That's a little closer to the truth.
 
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