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lehpron
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Would A 320 Mph Takeoff Speed Be Acceptable?

Sat May 17, 2003 10:24 am

First question in your minds has got to be, "to whom?"

Aside from outright responses, is it acceptable provided that it had a reasonable take off field length and noise levels were regulated properly?

Obviously if a plane needed such a high speed for lift, it would have to really pin passengers just to get it out of the airport altogether, thus probably creating a unheard of level of noise -- which by regulation would not have let it exist in the first place.

But if it were within regulation (which is what I meant by acceptance), would you care [any less]?


Please refrain from likelihood ideologies.
The meaning of life is curiosity; we were put on this planet to explore opportunities.
 
MD88Captain
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Sat May 17, 2003 10:54 am

Regardless of the obvious limitations of such an event, no tire could withstand the heat such a takeoff would produce.
 
Ralgha
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Sat May 17, 2003 10:57 am

They've broken Mach 1 with a car, what kind of tires did they have?
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ryu2
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Sat May 17, 2003 10:59 am

As a passenger, it would be fun for me, ha ha! But maybe not for older people with health problems.
 
BlatantEcho
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Sat May 17, 2003 11:02 am

the cars that break the sound barrier certainly do not use rubber tires

I believe it is some metal alloy, titanium, aluminum type of stuff.

Where did 320mph come from anyway?

George
 
flyf15
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Sat May 17, 2003 11:03 am

Ralgha, they had solid metal wheels.

Along the lines of what MD88 said, no brake could withstand the heat from an aborted takeoff at those speeds.
 
IMissPiedmont
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Sat May 17, 2003 2:03 pm

Why, oh why, do I suspect what you mean Lehpron? Yes, it is feasible, as long as you have a 27000 ft runway. As far as I know, there are only 3 of these in the world. One is semi-public knowledge, the other two I will not say.

 Smile/happy/getting dizzy
The day you stop learning is the day you should die.
 
Guest

RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Sat May 17, 2003 2:32 pm

To answer your question... NO ! ! !
 
IMissPiedmont
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Sat May 17, 2003 2:45 pm

To answer your question, yes!!!

Acceptable to who is the question.

It's indeed been proven to be feasible, just limited..

Don't ask because I will not answer.
The day you stop learning is the day you should die.
 
lehpron
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Mon May 19, 2003 12:37 am

Gosh I totally forgot about the wheels and brakes. But landing and takeoff, even at these projected speeds, would still be less than 35 seconds. Would the tires just melt or deform? Surley the carbon disk brakes would just smell like something died. What about with more wheels available, could there be less stress/heat absorbed per tire?

sorrie 'bout the techie questions.

The meaning of life is curiosity; we were put on this planet to explore opportunities.
 
buckfifty
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Mon May 19, 2003 1:40 am

For a tire to withstand that kind of heat, it'll probably be hard as a rock, and not very comfy for the passengers. Even the space shuttle only lands with speeds around 200 kts or so, nowhere near the figure you mentioned.

And as for takeoff at those speeds, is it really necessary? Can't think of any practical reasons why you would need such an a/c, unless if it's a spaceplane type of deal with poor lift characteristics...
 
Rick767
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Mon May 19, 2003 6:52 am

It's not takeoff distance which is usually the limiting factor but Accelerate-Stop Distance (ASD).

One question which therefore springs to mind.. if the s**t hits the fan at 319mph, how the hell are you going to stop it? The braking energy (without use of reverse thrust as this is not allowed to be counted) would be enormous and the runway length required would be similarly obscene...

So no, can't be done without some serious runway length extensions.
I used to love the smell of Jet-A in the morning...
 
sovietjet
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Mon May 19, 2003 12:03 pm

I dunno what plane you guys mean but in the USSR a Mig-23 took off at about 560 km/h which would equal to 350 mph. Reason being the pilot forgot to move the wing to takeoff position. The Mig-23 wing should be at 16 degrees for takeoff but the pilot had it at 72 degrees. After inspection of the aircraft the tires were just fine without any damage...Not once did a Mig-23 take off at such a high speed because 72 degree takeoffs happened once in a while. Of course that is a fighter jet and you guys might mean something else like a B-777.
 
POSITIVE RATE
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Mon May 19, 2003 12:39 pm

The space shuttle probably has the highest landing speed out of any aircraft. I think touchdown speed is somewhere in the vicinity of 180-190kts. Even at that speed the tyres and brakes heat up considerably- in fact it uses a braking chute to help slow it down. 320mph is just ridiculous- imagine the runway length required. Plus a plane that requires 320mph minimum to take off must have a really really really crappy designed wing which produces almost 0 lift- even a delta wing which is a pretty low lift producing wing doesn't require anywhere near that speed.
 
sovietjet
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Mon May 19, 2003 11:53 pm

The runway length would indeed have to be long but not impossibly long because the plane accelerates somewhat exponentially meaning it won't take that long to reach 320 mph.
 
BeltwayBandit
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Tue May 20, 2003 12:09 am

As soon as you were in the air, you'd be violating regs on airspeed!
 
bobrayner
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Tue May 20, 2003 12:44 am

With the most simple dynamics - uniform acceleration and a stationary start - the distance covered is:
s = 0.5 * a * t^2

In other words, accelerating for twice as long means you need 4 times as much runway.

The runway length would indeed have to be long but not impossibly long because the plane accelerates somewhat exponentially meaning it won't take that long to reach 320 mph.

If you want to get a linear relationship between takeoff speed and distance, you'd need engines capable of providing exponentially increasing thrust (whilst still on the ground) as the speed increases, no?

All the above applies for braking, too. Braking uniformly from 320 to 160 (with a given braking force) will cover 3x the distance of braking uniformly from 160 to 0 in the same conditions; so the total is 4x the distance, to brake from 320 to 0. Dealing with the heat (4x the energy) is not impossible, but would presumably need some very clever engineering.

All this ignores drag, of course. I doubt that drag works in your favour.  Wink/being sarcastic

Therefore, I'll assume that doubling the speed means quadrupling the ABD, unless anybody has better (empirical) figures
Cunning linguist
 
707CMF
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Tue May 20, 2003 12:53 am

Please, maintain 250 knot under 10,000 Ft.
320 mph = 278 knot.

If you know any airport over FL100, then yer, it's okay.

But at that altitude, you might need a hell of a runway !

Antoine

[Edited 2003-05-19 17:53:56]
 
BeltwayBandit
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Tue May 20, 2003 2:15 am

La Paz Bolivia, with rocket boosters?
 
XFSUgimpLB41X
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Tue May 20, 2003 4:05 am

Besides the lunacy of this idea.... heavy jets get cleared to acclerate to over 250 KIAS below 10,000 feet all the time so they can clean their wings up.

The wheels would have to be some sort of metal and rubber combination, not to mention brakes you couldn't imagine.

My question is...how on earth did you arrive at 320 for a takeoff speed? Just use high lift devices to slow the thing down.
Chicks dig winglets.
 
IMissPiedmont
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Tue May 20, 2003 12:29 pm

Military aircraft are not limited below 10,000 feet.

And who it would be acceptale to is indeed the qeustion. Airliners and civilian operators obviously not. But military? Oh yea.And comfort is not known as a large part of military operations so tires hard as a rock are irrelevant.

I know of 3 paved 25000+ foot military runways in the US and they were not built for fun. ASD is the answer.
The day you stop learning is the day you should die.
 
sovietjet
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Tue May 20, 2003 2:02 pm

mig-23 took off at 350mph on a 3200m runway equals to about 8800 feet...but that's with afterburner and 18 degree pitch at the end of the takeoff run plus it was empty and wasn't carrying any extra fuel. I think the only thing it was carrying was an R-60 missile imitator. However, since the wing was at 72 degrees, the flaps were not down at all. Still pretty impressive reaching a speed of 350 mph in just 8800 feet. Even less than that because it didn't take off at the EXACT edge of the runway. The plane lifted off with about 200-300m remaining which would come to a total of about 8000-8300ft....
 
JBirdAV8r
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Tue May 20, 2003 11:23 pm

As soon as you were in the air, you'd be violating regs on airspeed!

Actually, you wouldn't. If going above 250 knots is required for normal (and safe) operation of the aircraft, the FAR's even state that the 250 under 10k rule does not apply.
I got my head checked--by a jumbo jet
 
apathoid
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Wed May 21, 2003 2:19 am

Is no one going to bring up how you abort the take off and get the airplane stopped if you are anywhere near V1?
 
Rick767
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Wed May 21, 2003 3:18 am

Apathoid,

I brought that topic up in reply #11 to this post (see above).
I used to love the smell of Jet-A in the morning...
 
apathoid
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Wed May 21, 2003 3:22 am

I apologize Rick...somehow I missed that.
 
lehpron
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Why...JIC

Fri May 23, 2003 7:52 am

I sure you guys are wondering why I posted this. Here's the thing: I am working on an odd high speed airliner currently (college hobby project) for the past few months:

* design MTOW set at 500 metric tons, chances are it may rise, but I've set a minimal max of 400 metric tons just so I have some leway.

* planform is a flying wing. where the wing is a delta, but with the required cruise conditions, it is swept back to 80 degrees.

* the size of the plane is similar to the stretched A380, 80.01 meters in length (i don't think anyone will gripe about a centimeter...) There can be a shorter version, but I risk loosing wing area doing so; which btw, the area is 8500 sq. ft.

Plus I have an odd airfoil, one that is designed to lower the boom pressure, giving the impression of a slower airplane to the person on the ground. It's lift coeffecient is between 0.29 - 0.43 and doubles at a 8-degree angle of attack. In the end, I get a T/O speed approaching 300mph, that's why I asked started this thread question.



Although I almost do not understand the runway length issues. This plane will NOT accelerate at standard airliner rates, obviously it has to have a high acceleration just to operate in most airports. This aircraft will be capable of a half gravity acceleration, the equivalent of 0 - 60mph in 5 seconds for 30 seconds. Believe me, it wont spend enough time to melt the tires and it wont take up more than 10000 feet in the process.


Hopefully this will help rather than hinder this thread, ask away if you wish.
The meaning of life is curiosity; we were put on this planet to explore opportunities.
 
bobrayner
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Fri May 23, 2003 8:42 am

Hmm.

Setting aside the question of how you can swing-wing when the wing is most of the aircraft...

How are you going to get >500,000lb of thrust?

Plus, you'd still need a large ASD; braking isn't going to be easy...
Cunning linguist
 
apathoid
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Fri May 23, 2003 8:54 am

The wheels and tires won't take it dude. Ain't no way. Emergency braking has to be considered and no braking system or tire for that matter is capable of absorbing that much energy. Certainly not at the weights you are describing.

Now I come to a clearer understanding of why it is us wrenches dont' like you engineers...
 
FredT
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Fri May 23, 2003 7:59 pm

Braking is not the only consideration as far as wheels go. The centrifugal forces ("lack of centripetal force", yada yada) can have a detrimental effect on tires spinning too fast (IOW, they go "BOOM!"), no matter how long they spin. Kevlar tires?  Smile

Apathoid,
good engineers have visions but keep their feet firmly planted in reality. I don't know if the worst engineers are those with visions but no contact with reality, or those without either...
One of the best parts of my job is that I have a hangar filled with some of the best techs there are next door. If I do something stupid, I'll know it within a day. Big grin

Cheers,
Fred
I thought I was doing good trying to avoid those airport hotels... and look at me now.
 
sovietjet
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Fri May 23, 2003 11:43 pm

What if he puts as much wheels as an An-225 after all they have around the same max takeoff weight? Only problem would be that he would need to make them of some other material than the An-225. As for the engines doing 0-60 in 5 sec I doubt any engine combination would achieve that. Many cars dont even achieve that acceleration. I think the engines are a bigger problem than the wheels and brakes. There are many ways you can stop the plane. Parachutes, conventional brakes, reverse thrust, spoilers, wheel brakes...all combined. This is just my opinion correct me if I'm wrong.
 
aer lingus
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Sat May 24, 2003 3:03 am

Try using 1 metre thick slicks  Big grin  Big grin
Split Scimitar or Sharklets?
 
lehpron
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Sun May 25, 2003 7:15 am

Bobrayner, do not confuse Sovietjet's issue, his point was with t/o speed, there is no swinging wing on this plane, it is just a steep delta wing.

Although with regard to Sovietjet's suggestion of more wheels, I already planned a 20-wheel setup where they are a little over a meter in diameter, all are able to have their tires changed with ease. I thought of, but not entirely of how to install, magnetic braking instead of carbon disks. Magnetic brakes are what some trains use, they do not have contact with the wheel. They weight tens of thousands of tons, but they take miles to slow (i think it's cuz they wiegh so much.) a 500T plane would not take so much. Airflow around the gear set would cool it.

You guys can try this with a strong permanent magnet and a pizza cutter.

"As for the engines doing 0-60 in 5 sec I doubt any engine combination would achieve that. Many cars dont even achieve that acceleration."

Except for my friend's '69 mustang or fighter jet engines with afterburners lit or an F-22 engine without, the point is to simply have enough thrust, I just don't like the noisy aspect. Even if there was a jet with a bypass ratio of 10 (or something else undeveloped, forget the costs) with thrust totaling a million newtons static, that sucker is gonna be loud as hell. Heck forget the vibrations at takeoff...

Still, I was thinking of two engines, but if I have to put 4 I don't know where to stick'em, there is only 25 meters of wingspan to play with, plus there needs to be a place for control surfaces. Right now I have two flying rudder surfaces, four elevon flaps and a pair of retractable canards. Maybe I can pull the t/o speed down to 290, but still...personally I would rather set the speed cap to 300.


Of course...I do not even want to say this, but...I could lower the main landing gear and increase the wing's angle of attack, doing so could bring the t/o speed into the lower to mid 200's, BUT it would look ugly. I am kind of an asthetic perfectionist, I would prefer to leave the over planform as it is. But then I do not like the high t/o speed either and the plane will get heavier, they always do.  Angry

Costumers are always more interested in asthetically pleasing products, making it ugly goes against its benefit. I am confident it'll work, it looks ugly already, I don't want to make it fugly.
The meaning of life is curiosity; we were put on this planet to explore opportunities.
 
XFSUgimpLB41X
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Sun May 25, 2003 3:27 pm

"You guys can try this with a strong permanent magnet and a pizza cutter"


I think a 1 million pound airplane has a bit more momentum than a pizza cutter...


Try some slats/flaps and such at least..not to mention extending the landing gear.. i mean, sheesh. Don't you think that extra 100 knots slower takeoff speed will help things a bit? Passengers could care less if the airplane is a bit ugly if they dont have to pull 5 G's on takeoff.

One word: practicality.
Chicks dig winglets.
 
POSITIVE RATE
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Sun May 25, 2003 6:01 pm

Yeah that's what i thought all along. Just use flaps/slats and your takeoff speed won't be anywhere near that. If your rotation speed is 320mph then imagine your approach and landing speed. 1 landing and your tyres would be gone, same as your brakes probably unless you had super efficient reverse thrust.
 
J32driver
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Sun May 25, 2003 11:19 pm

Whats the wingspan? If its large, how do you plan on moving the thing around congested airports on tight taxiways?

How are you going to park it... will a standard jetway mate to your flying wing?

Use high lift devices to lower the Take off speed. If you don't like the looks of flaps and slats, how about a vacuum system to suck down the boundary layer and allow a higher AOA? (F-16XL test bed!!)
 
FredT
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Mon May 26, 2003 3:39 am

If it is a delta, high AoA shouldn't be a problem. Drag at a high AoA would however. Hmm... how about making the rear landing gear part of the control system? Accelerate with the aircraft in a nice-looking level attitude, then lower the gear to get the high AoA and ugliness to repulse the ground.  Big grin

Not reading too closely, but I recall flying wing design being mentioned. Getting it certified will be a nightmare. Evacuation has to be considered, noone is interested in moving cargo at supersonic speeds. Oh well, except for those wannabe wine freaks with more money than good taste who are desperate to get the first bottles of the year flown to NYC and Tokyo - even if they taste more like CC than wine!

Many reasons it'll never happen. OTOH, dreams and visions are what bring the world forward. Many great inventions would never have been certified in their initial states and under the then current regulations. And even if it is not a great invention, much can be learned from nutty ideas and projects. I if anyone should know...  Big grin

Cheers,
Fred
I thought I was doing good trying to avoid those airport hotels... and look at me now.
 
lehpron
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Fri May 30, 2003 12:49 am

"Accelerate with the aircraft in a nice-looking level attitude, then lower the gear to get the high AoA and ugliness to repulse the ground"

That is a very nice idea, doesn't the carrier-born Rafale have that on its nose wheel? I can't imagine the stress levels on a main landing gear set that moved vertically as the aircraft rolled for t/o.

let me try to make one thing clear: this plane is a flying wing in the sence that all of the planform surface creates lift, however it has a delta shape overall, not like a B2, consider it more like a high-speed blended-wing-body. its length to span ration is pretty steep, 3:1; i don't know how strong the vortices would be...
The meaning of life is curiosity; we were put on this planet to explore opportunities.
 
SSTjumbo
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Fri May 30, 2003 12:42 pm

I'm probably BSing, but don't winglets reduce wingtip vortices? If this be the case, Lehpron, couldn't you incorporate some sort of winglets at the wingtips, even ingrain rudders into them? Remember, just because it's a flying wing doesn't void it from yawing errors. Going back again to the B2, that airfoil used drag rudders to coordinate the movements of the aircraft, almost looking like spoilers on the ends of the wings [picture, please?]. Somehow, I think using real rudders would be somewhat more efficient than drag rudders, even if they were small and had to be used in conjunction with smaller drag rudders. Then again, this doesn't have anything to do with wingtip vortices Embarrassment. Just a thought though, good luck.

Cheers
-Mike
I don't know, so this is my signature.
 
L-188
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Fri May 30, 2003 4:36 pm

That Mig-23 story is just crazy enough to be belived but I do have to speculate that in a western air force there would have been a minumum of a tire change to that airframe.

I wonder if there are some simular stories about F-111, Tornado or F-14 drivers doing the same thing?
OBAMA-WORST PRESIDENT EVER....Even SKOORB would be better.
 
lehpron
Topic Author
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Sat May 31, 2003 12:42 am

"I'm probably BSing, but don't winglets reduce wingtip vortices? If this be the case, Lehpron, couldn't you incorporate some sort of winglets at the wingtips"

this would make sence on high aspect ratio wings, what about low aspect ratio wings? Would the drag be reduced on Concorde if winglets were added? that's my point, thia plane is mainly a flying delta wing, think about it.
The meaning of life is curiosity; we were put on this planet to explore opportunities.
 
FredT
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Sat May 31, 2003 2:00 am

As the vortices shed along the entire leading edge on a delta wing, and are effectively what causes the lift - no, winglets would probably not do a lot of good.  Smile

Cheers,
Fred
I thought I was doing good trying to avoid those airport hotels... and look at me now.
 
cedarjet
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Sat May 31, 2003 4:13 am

Miss Piedmont: "...as long as you have a 27000 ft runway. As far as I know, there are only 3 of these in the world. One is semi-public knowledge, the other two I will not say." And so on. Gosh, so many, "I could tell you but then I'd have to kill you" contributions from you! Come on, if you were in possession of real classified info you wouldn't be hinting at it like crazy every fifth post down, you'd keep it zipped. So spill the beans, you know you want to.
fly Saha Air 707s daily from Tehran's downtown Mehrabad to Mashhad, Kish Island and Ahwaz
 
POSITIVE RATE
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Sat May 31, 2003 10:47 am

How long is the runway at the shuttle landing facility used for shuttle landings? Surely that must be in the top 5 longest?
 
IMissPiedmont
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Sat May 31, 2003 12:55 pm

Actually not, Cedarjet. I do know of three such runways, all of which a person could find easily on the internet. Just as a person could find out where the Mig-29s were based when first given to the US Air Force. No, I would not have to kill you, I just can't say. It's not such a big deal, just rules that I agreed to many years ago.

For instance, I have a friend with the same security clearance as I, yet we cannot discuss certain things that we both know we know. Silly isn't it.

 Smile/happy/getting dizzy

PS: We have quite similar conversations in person.
The day you stop learning is the day you should die.
 
XFSUgimpLB41X
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Sat May 31, 2003 1:01 pm

The shuttle landing facility is 15,000.
Chicks dig winglets.
 
MxCtrlr
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Sun Jun 01, 2003 12:01 am

I see another potential problem with this concept, in relation to conventional runways during an RTO. Assuming the worst case scenario, an RTO at just shy of V1, the passengers and crew would be turned into jelly from the deceleration forces needed to stop the aircraft within the constraints of a conventional runway (assuming you wanted to keep the damn thing on the pavement that is  Smile)!

MxCtrlr  Smile/happy/getting dizzy
Freight Dogs Anonymous - O.O.T.S.K.  Smokin cool
DAMN! This SUCKS! I just had to go to the next higher age bracket in my profile! :-(
 
lehpron
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Sun Jun 01, 2003 12:40 am

my estimate are that we need 7500 feet from brake release to /to speed and from there back to zero add another 7000 feet. I think this could fit into major airports, where it would operate from anyways. Although with deceleration at the same but opposite rate of acceleration, it would be like the Superman ride at 6 Flags Magic Mountain in California. How bad is that?
The meaning of life is curiosity; we were put on this planet to explore opportunities.
 
flyf15
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Sun Jun 01, 2003 4:23 am

Well, theres always the SR-71. Your 320mph equates to just under 280kts. The SR-71 begins rotation around 180kts and lifts off while passing trhough 210kts. Overspeed is 300kts. So, it is acceptable, somewhat. Depending on who you are, afterall.
 
sovietjet
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RE: Would A 320 Mph Takeoff Speed Be Acceptable?

Tue Jun 03, 2003 12:57 am

"Except for my friend's '69 mustang or fighter jet engines with afterburners lit or an F-22 engine without, the point is to simply have enough thrust"


Damn that must be a hell of a Mustang. Have you ever seen that video where an F/A-18 and a F-1 racing car drag race. The F-1 accelerated like hell but got beat in the end when the plane's speed became way bigger. Anyway back to the topic. I think those magnetic brakes you were talking about are a good idea except that they are heavy. Can those be combined with regular carbon brakes? A million pound plane is a huge thing but a combination of braking devices should be able to stop it properly on landing. However, what would happen if there should be an emergency landing right after takeoff where the plane would have to land at max weight?

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