Why can't Jet planes fly in space?

In summary, jet planes cannot fly in space because they require atmosphere for lift and to produce thrust. A jet engine works by using oxygen from the air to combust with fuel, while wings work by creating lift from airflow. However, in space, there is no atmosphere, so a jet engine cannot function properly. A spacecraft, on the other hand, has a self-contained propulsion system and does not rely on atmosphere for lift or thrust, allowing it to travel independently in space.
  • #1
Arjun Ar
19
0
Why can't Jet planes fly in space?

Is is because it doesn't get lift or is it due to the absence of atmosphere?
 
Astronomy news on Phys.org
  • #2
What is a jet engine? How does it work?
 
  • #3
And wings. How do they work?
 
  • #4
Borek said:
What is a jet engine? How does it work?

D H said:
And wings. How do they work?

That's the difference between chemist and physicist :rofl:
 
  • #5
I guess you guys have not seen "Airplane II" :smile:
 
  • #6
Arjun Ar said:
Why can't Jet planes fly in space?

Is is because it doesn't get lift or is it due to the absence of atmosphere?

What is the relationship between lift and atmosphere. Your statement seems to imply that they have nothing to do with each other. Is that what you believe?
 
  • #7
Of course, you don't really need "wings" or "lift" in space. What you need is thrust. The difference between a jet engine and a rocket engine is that the rocket engine contains its own oxygen (perhaps in the form of a chemical) while a jet engine gets its oxygen out of the air.
 
  • #8
A jet could fly in space. It couldn't produce thrust, maneuver, or keep the cabin pressured in space. Use a rocket to put it into orbit and it will fly until gravity eventually pulls it back down. The strict definition of flying is to move through the atmosphere and there is most certainly atmosphere in orbit.
 
  • #9
NumericalPain said:
A jet could fly in space. It couldn't produce thrust, maneuver, or keep the cabin pressured in space. Use a rocket to put it into orbit and it will fly until gravity eventually pulls it back down. The strict definition of flying is to move through the atmosphere and there is most certainly atmosphere in orbit.

Depends on how high the orbit is. Above the atmosphere, it would be in a ballistic trajectory and I don't think traveling in a ballistic trajectory is considered flying. It would no more be flying than the moon is flying.
 
  • #10
NumericalPain said:
. The strict definition of flying is to move through the atmosphere and there is most certainly atmosphere in orbit.

The heights that satellites orbit have almost no atmosphere. That's actually one of the points, with minimal atmosphere, satellites don't need to carry as much fuel to compensate for constant frictional forces slowing it down.
 
Last edited:
  • #11
HallsofIvy said:
Of course, you don't really need "wings" or "lift" in space. What you need is thrust. The difference between a jet engine and a rocket engine is that the rocket engine contains its own oxygen (perhaps in the form of a chemical) while a jet engine gets its oxygen out of the air.

If oxygen is the problem, what if we use some other fuel that doesn't require oxygen for burning? Could we fly the jet plane in space?
 
  • #12
Arjun Ar said:
If oxygen is the problem, what if we use some other fuel that doesn't require oxygen for burning? Could we fly the jet plane in space?
No. They don't carry enough fuel, have enough thrust or the ability to maneuver in space.
 
  • #13
Arjun Ar said:
Why can't Jet planes fly in space?

Is is because it doesn't get lift or is it due to the absence of atmosphere?

Greetings Arjun Ar,

Jet engines employ an “open system” method of propulsion therefore they require the high velocity airflow of atmosphere through their turbine engines from which they make use of its oxygen to allow combustion with the fuel the carry. Additionally, airflow is required to produce lift as well as provide axis control of the jetliner.

Conversely, a spacecraft employs a “closed system” method of propulsion whereby all the elements necessary to produce thrust for acceleration and axis control of the spacecraft are self-contained aboard the spacecraft thereby making its ability to traverse a desired expanse of space 100% independent of its surroundings.
 
  • #14
It depends on what you qualify as "space."
The US has developed the SR-71, which allowed the pilot to see the curvature of the Earth and the blackness of space. There was still, admittantly, a little atmosphere left.
:D
 
  • #15
Arjun Ar said:
If oxygen is the problem, what if we use some other fuel that doesn't require oxygen for burning? Could we fly the jet plane in space?

At the point that you carry all your fuel on board, the "jet engine" becomes a rocket.

The broad definition of a jet engine DOES include a rocket engine, however, so yes, a "jet" engine could indeed fly in space. However, not the more specific turbofan or turbojet that you're thinking of, whose operations rely on an atmosphere with oxygen.
 

1. Why can't jet planes fly in space?

Jet planes rely on air for lift and propulsion. In space, there is no air for the plane's engines to push against, making it impossible for the plane to move forward or stay aloft.

2. Can jet planes be modified to fly in space?

No, jet planes are not designed to withstand the extreme conditions of space, such as high levels of radiation and lack of atmospheric pressure. Modifying them to fly in space would require a complete redesign, which is not feasible.

3. What about rockets, why can they fly in space?

Rockets use a different propulsion system called rocket propulsion, which does not rely on air for thrust. Instead, they carry their own oxidizer and fuel, allowing them to generate thrust in the vacuum of space.

4. Can jet engines work in space?

No, jet engines require a constant flow of air to function, which is not present in space. Without air, the engine cannot produce thrust and would not be able to propel the plane forward.

5. Is there any type of aircraft that can fly in space?

Yes, there are specialized spacecraft designed to fly in space, such as space shuttles and spaceplanes. These vehicles use a combination of rocket propulsion and aerodynamics to fly in the Earth's atmosphere and beyond.

Similar threads

  • Aerospace Engineering
Replies
10
Views
1K
  • Astronomy and Astrophysics
2
Replies
37
Views
5K
  • Classical Physics
Replies
23
Views
373
  • Astronomy and Astrophysics
Replies
7
Views
2K
Replies
12
Views
278
  • Astronomy and Astrophysics
Replies
22
Views
2K
Replies
4
Views
4K
  • Other Physics Topics
2
Replies
36
Views
4K
  • Astronomy and Astrophysics
Replies
5
Views
3K
  • Classical Physics
Replies
6
Views
657
Back
Top