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Why do (jet) airplanes fly at tropopause (and not higher) [duplicate]

I've got a question which is nearly answered by the following thread however not fully to my satisfaction. Why do jet engines get better fuel efficiency at high altitudes? The question ultimately ...
354 views

Is it the engines or the fuselage that limits service ceiling? [duplicate]

Reading this article about the Northrop Grumman E8 it says the the aircraft will be able to fly higher after engine upgrades. Wouldn't the max service ceiling be limited by the fuselage design too?
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What happens if an aircraft goes above maximum altitude? [duplicate]

We all know what happens when a plane goes overspeed... but what happens when a plane goes above their max. altitude? And why are planes certified maximum altitudes anyway? Is it because there won't ...
548 views

Can a commercial aircraft theoretically reach 60,000ft? [duplicate]

As per this question: Altitudes above 60,000 feet are class E airspace. That means that, if you are lucky enough to have an aircraft that flies that high, once you get there you could theoretically ...
483 views

Calculating the maximum altitude of a drone [duplicate]

Is there an equation to find the maximum altitude that a drone or quadcopter can fly to ?
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Why is the F-16's service ceiling 50,000ft? [duplicate]

What defines the service ceiling for aircraft, in particular the F-16? I suppose, as with almost everything, this depends on the aircraft, the engine type, etc. While I'm fine with a comprehensive ...
9k views

Why are many jet aircraft designed to cruise around FL350-370?

If the flight distance permits, the B737-800 will cruise at FL350, the A320 a little bit higher... Flying at FL370. Photo: Live from the Flight Deck by GolfCharlie232 (reframed) Elements such as ...
30k views

Why can't jet engines operate with supersonic air and how do they slow it down?

Typically jets cannot operate when intake airflow is supersonic relative to the engine. Why is this so? Also, why are scramjets able to use supersonic air? To slow down the air to subsonic speeds, ...
21k views

What is a high speed stall?

I'm told that planes can actually stall when the airflow over the wing goes past Mach 1? Why does this happen and how do you design an aircraft to avoid it?
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What are the limiting factors for high altitude planes (e.g: U2 or SR71) preventing them from going higher?

I'm curious as to why planes like the U2 Dragon Lady and the SR71 Blackbird couldn't fly higher. What physical constraint set their operational ceiling? Pilots wore spacesuits, so that wasn't the ...
29k views

How high can propeller airplanes fly?

Is there a maximum height a propeller airplane could fly? Some lower bounds for maximum flying altitude: 12,000m (39,370ft): Antonow An-70, produced 1994 12,310m (40,387ft): Lockheed Martin C-130J ...
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Why would a Su-25, which has more power and is much lighter than an A-10, only fly half as high?

On the web, on several sites, the A-10 is listed with a ceiling of 14 km, the Su-25 with 7 km, although there is data that puts the height for the Su-25 at 10 km. Nevertheless, why would the Su-25 ...
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Is the climb rate different for short-haul flight and long-haul flight?

A short-haul flight does not spend much time in its cruise level (let's say less than two hours). Thus, it is important to rapidly reach the optimal flight level and I think this kind of aircraft ...
3k views

At what altitude does aerodynamic forces become negligible?

If I sail on a boat from North to South the boat will be dragged by the oceans which it floats on, and the oceans are dragged by the Earth. Now when you go higher let say 10 km an airplane will also ...
916 views

Are there any aircraft designed to operate between an altitude of 50-80km?

Aircrafts operating at high altitude falls into several categories: Wings with high aspect ratio (Global Hawk, TR-1, Scaled Composite Proteus,...) High velocity aircraft (Concorde, A-12, X-51,...) ...
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What are the limiting factors when flying a model UAV plane to high altitude?

Setting aside the likely legal factors for a moment, what are the limiting factors when flying a model plane to high altitude? As I see it these could be: Battery power consumption - Model planes ...
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I'm thinking of building a balloon-launched glider, is this idea plausible?

So, I know nothing about aviation. I'm a student studying maths and computing and I feel like building a high altitude glider controlled by a Raspberry Pi and Arduino as a personal project. First ...
667 views

What should be the minimum time spent in cruise (for e.g. a B737)?

Having a short sector to fly, it would not be convenient to climb all the way up to the best cruise altitude, since the time in climb would burn more fuel than that necessary for a flight at lower ...
710 views

How could a PA-28 be made to fly higher?

How would I have to modify the Piper PA-28 to fly at 25,000 feet (same as PA-34 and PA-46)? Could it fly higher? Larger wings, other wingform, bigger motor something else? Do you have to change the ...
415 views

May planes be flown above the maximum certified altitude?

Let's take the 737NG as an example. The 737NG has a maximum certified altitude (MCA) of FL410. However, looking at the MCP, the maximum altitude that can be set is 50,000ft. And the pressurization ...
224 views

What happens in an F-16 once the aircraft exeeds its service ceiling?

What exactly is the sequence of events that would unfold as an F-16 attempts to exceed its service ceiling? The scenario is simply full afterburner and attempting to simply climb higher and higher (at ...
This question What determines the maximum altitude a plane can reach? has a formula at Peter Kämpf's answer : $$\rho_{min} = \frac{2\cdot m\cdot g}{(Mach^2 \cdot c_L)_{max}\cdot a^2\cdot S}$$ Does ...