Fastest Commercial Jetliner. Options

[alex-y]

You just keep missing it - the "speed" aspect isn't what the 787 is all about - it's ECONOMY (and the two, like in AUTOMOBILES don't coincide - more speed, more fuel usage) No - it won't be "the fastest"

he he. my bad. I was told it was going to be the fasted jetliner. I guess he was wrong. well i was checking up on 787 facts and it says it cruising speed will be mach 0.85 . thanks for the info though

[Intergalactic]

So I guess everyone has answered pretty much every questions...But I have some things to add and hopefully they are correct in some way. Otherwise the wiser than me could correct me if I am wrong.

So about the 747 t/o with just one engine. There might be a good possibility it COULD takeoff with one engine, but I don't think pilots would want to be in that situation. Not to mention the force of one of those engines would cause a kind of crosswind effect and more rudder would have to be applied. And just to point out, IF under that circumstances a 747 has to use one engine to t/o, remember the max takeoff weight of the aircraft. That max t/o weight is combined with the engines. Therefore, if stated the max t/o weight of a 747 is 800,000lbs, then most likely the manufacturer means that IT is recommended that all 4 engines do their job. As I have researched, a boeing 747 uses 4 Pratt and Whitney engines, Rolls Royce engines, or even General Electric engines designed to produce about 60,000lbs of thrust. Therefore, if you try to lift a fully loaded 747, or even a half loaded 747, the rate of speed ascending off the scale would be much lower. That means you gain speed alot more slowly. So, consider this, slow speed gainings, plus a pretty heavy weight capacity on the flight, and to add the weather conditions equals a pretty disasterous situation. #1) The aircraft wouldn't lift off the tarmac in time and overruns the end of the runway, or #2) Aircraft tries to lift off, but clips off the fencing with its gears. Of course, this situation wouldn't happen ALL of the time. But that is just my opinion.

So you are telling me a 747 can takeoff with just 2 engines on and the other 2 off? I won't disagree with you about it taking off. But consider the dragging the other 2 engines would cause. What does this mean? More fuel comsumption during the climb. Because dragging effect is in place while 2 engines are off, the other 2 engines has to work even harder to try to keep the aircraft climbing like normal. Thus taking away the meaning of efficiency.

And the 787 isn't designed for speed. Surely it could be new, but that doesn't mean its performance in speed wouldn't be slower than other aircrafts. Remember, the 787 is designed to be efficient with noise reducement for the pax. And to the word "efficiency", I mean that the 787 has increased range other than its brothers and sisters. And besides, why would you want to get to your destination faster anyways, don't you just love the joy of airplanes?

No aircraft is overpowered. The extra power is there to give the aircraft the boost it needs to perform its duties. Look at what we have now. Say a 747 for example, using all 4 engines, it could rotate with the engines not at full power. But on a very heavy flight, pilots know that 4 engines on the 747 wouldn't rotate in time when the engines are not at full power. So they add that extra energy that is spared for the aircraft so that they could resume their normal procedures.

As stated, anyone feel free to correct me in anyway....

Cheers!

IG

[Fluffdoc]

Wise airplane manufacturers try to avoid putting any more power on an airplane than needed to accomplish the expected mission with some safety margins applied. Excess power (i.e. hanging a 767 on a 757) increases weight and fuel burn which increases cost.

As for the 747, you cannot legally takeoff with two engines inoperative - period (unless you lose them after V1 which I have never heard of). You can take off with one engine inoperative but only as a ferry flight and with a ton of restrictions on things like runway length, climb, cruise speeds, weight, and such. If you think I'm making this up, refer to the 747 Airplane Flight Manual which is the bible for operating the airplane. It is very specific as to the restrictions related to engine-out takeoffs.

[AspiringPilot]

Well just because a 747's enginges are strong it doesnt mean they make they plane go really faster in the long run. So lets say the plane accelerates in the begining of the flight. Yea and its moving fast. Then half way over the altantic theirs going to be a depression in how much fuel to be used and whats supposed to be used. Then the pilot is going to have to slow the plane down. So it can depend on how the tail winds and wind direction and a few other variables..... Well I was wondering. Wouldnt the altitude the 747 flys at effect its speed? Since I hear that they can fly at high alts? And air pressure at higher alts is lower. Allowing the plane to move faster.

[Archangel]

Well just because a 747's enginges are strong it doesnt mean they make they plane go really faster in the long run. So lets say the plane accelerates in the begining of the flight. Yea and its moving fast. Then half way over the altantic theirs going to be a depression in how much fuel to be used and whats supposed to be used. Then the pilot is going to have to slow the plane down. So it can depend on how the tail winds and wind direction and a few other variables..... Well I was wondering. Wouldnt the altitude the 747 flys at effect its speed? Since I hear that they can fly at high alts? And air pressure at higher alts is lower. Allowing the plane to move faster.

Yea you can go faster the higher you get, but you will reach a breaking point long before your optimal cruising alt. Between 20,000 and 30,000 is where you can really haul butt. But at some point you will lack the power to maintain the Indicated airspeed to allow you to fly. For this reason the higher you go, the more nose high your plane flies. Also the higher you go the slower your IAS, while your groundspeed may be insane and even your mach the plane will be on the verge of stalling. The U-2 was a prime example, it had to be seriouly overpowered and have serious engine modifications to fly that high, yet it still had a small margin of error for stalling.

[glnflwrs]

It is a very telling thing when one resorts to addressing others with insulting, childish pronouns such as dumba** or moron. For the most part mature adults have long since totally eliminated these useless explitives from their vocabulary. It simply isn't needed and is detrimental to an mature agenda.

Ie: Grow up ya'll, we don't put up with that here.

[Dan_Taylor]

Does any airline still have the VC-10 in service (I doubt it, but I know the military still use it as a tanker), because that can cruise at mach 0.86 if I remember correctly.

Dan.

[Archangel]

It is a very telling thing when one resorts to addressing others with insulting, childish pronouns such as dumba** or moron. For the most part mature adults have long since totally eliminated these useless explitives from their vocabulary. It simply isn't needed and is detrimental to an mature agenda.

Ie: Grow up ya'll, we don't put up with that here.

Did i miss something?

[Going_around_aga...]

Does any airline still have the VC-10 in service (I doubt it, but I know the military still use it as a tanker), because that can cruise at mach 0.86 if I remember correctly.

Dan.

I dont think any airlines have VC-10s in service anymore.

Is it only the UK Air Force that use them?

[AspiringPilot]

Yea you can go faster the higher you get, but you will reach a breaking point long before your optimal cruising alt. Between 20,000 and 30,000 is where you can really haul butt. But at some point you will lack the power to maintain the Indicated airspeed to allow you to fly. For this reason the higher you go, the more nose high your plane flies. Also the higher you go the slower your IAS, while your groundspeed may be insane and even your mach the plane will be on the verge of stalling. The U-2 was a prime example, it had to be seriouly overpowered and have serious engine modifications to fly that high, yet it still had a small margin of error for stalling.

Oh thanks Mcchord. Yet another question that Id that Id push in. Why when double prop engine wing mounted planes are moving into land they always have a downard pitch.

[Dan_Taylor]

I dont think any airlines have VC-10s in service anymore.

Is it only the UK Air Force that use them?

Not too sure, but I think so yes. I'll do a little bit of research when I have more time on the computer - I'm only on for 10 minutes before I go out.

Dan.

[glnflwrs]

Did i miss something?

Mac,
Refer to post # 24, 25, 28, and further subsequent posts in this topic

.

[AIRCRAFT ENGINEE...]

Oh thanks Mcchord. Yet another question that Id that Id push in. Why when double prop engine wing mounted planes are moving into land they always have a downard pitch.

??? huh? prop pitch? attitude? downward? You mean why the landing aircraft is in an attitude with the nose toward the ground? Actually isn't - the flare is "nose up" otherwise is just "descent attitude"

I still haven't figured out exactly what you mean...

[karlhurst_380]

Yes Dan, Only the Royal Air Force remains to have VC-10's, I believe they are used for air-to-air refuelling.

[tripleseven]

It is a very telling thing when one resorts to addressing others with insulting, childish pronouns such as dumba** or moron. For the most part mature adults have long since totally eliminated these useless explitives from their vocabulary. It simply isn't needed and is detrimental to an mature agenda.

Ie: Grow up ya'll, we don't put up with that here.

Being one of the offenders, but not the initial offender........I totally agree