Aircraft (jet) questions?

Question

I have two questions about jets. The first being, why do some Jets have a point at the tip of the front? And what are those big tube looking things under Jets/Aircraft are they the fuel tanks?

If you're confused here are two pictures..

http://img181.imageshack.us/img181/3198/adadeb2.png
http://img253.imageshack.us/img253/3738/asdadps0.png

Thanks.

Answer 1

Both answers are pretty close. Those "tubes" are auxiliary fuel tanks. Not drop tanks. Drop tanks do not have lifting fins on them. They are just smooth in the back. Here is an A-4 with drop tanks http://www.avsim.com/pages/0801/a4c/banner.jpg

The Pitot tubes are correct seen at the front of those aircraft to measure air pressure and calculate speed. But they are at the front for a different reason than the one given. You notice you don't see them at the front of an airliner. The reason is the aircraft in your picture go past the speed of sound. a Pitot tube mounted past the nose of a supersonic aircraft would be made useless once you broke the sound barrier as the shock wave would push the air around it in a big "bow wave".

http://www.grc.nasa.gov/WWW/K-12/airplane/pitot.html

Good stuff!

Answer 2

Ugiidriver already mentioned the APU and ground units. The APU is really just a small jet engine most often located in the tail of the aircraft, with an exhaust port in the tail or somewhere else near the tail. It provides not only A/C but also electrical power before the main engines are started. If both engines failed up at 30,000 feet, the airplane's APU could be started and might be able to maintain the correct cabin pressures during the descent. But in practice this probably wouldn't happen. The pilots would instead put on their hi-flow oxygen masks, cross their fingers that passenger masks work, then put all their attention into getting the airplane safely on the ground, as soon as possible.

Answer 3

Yes, that tubes are external fuel tanks.
Some jets have a point on the front, usually if they are supersonic because this will generate a cone of shock and this helps supersonic flight, but sometimes also subsonic planes have a point on the nose, this because that point is a "pitot", that is the instrument needed to measure the airspeed, and to reduce the error it's better that the pitot is placed in undisturbed airflow, so it's best if it is placed at the biggest distance possible from the nose......in fact prototipes usually have a very long point...while points of aircrafts in service are usually shorter

Answer 4

The points are not for aerodynamics, they are the pitot tubes. These tubes capture the ram air caused by the forward motion of the aircraft to measure airspeed. They have been put far forward on these aircraft to ensure they are in air that is free of turbulance so they get the most accurate measurements.

The tubes on the pictures of the A-4's are indeed extra fuel tanks.

Answer 5

The A-4 max speed is 561 Knots Speed of sound is 661.7 Kts @ sea level. The A-4 is NOT supersonic. The pointy for good aerodynamics.The IFR probe ,(in flight refueling). is on Starboard side ( Pilot's right).about level with nose.Earlier A-4s ( E-model) have a bent IFR . F-model straight
.See reference:
http://www.globalsecurity.org/military/systems/aircraft/a-4-specs.htm
The tanks are external fuel tanks, ( up to 3 on A-4 ) The middle A-4 in 1st picture if fitted with the third tank ( center).

Answer 6

The big fat pointy things in the first picture are fuel tanks. The pointy things on the airplanes noses in the second picture are pilot tubes(measures airspeed).

Answer 7

The tip is so if a pilot has to go a long way he can be met by a tanker plane (which holds a TON af fuel, so it could travel all the way around the world) and refuel in mid air, that way they don't need aircraftcarriers to get to foreign countries.

the big tubes are bombs








TRUST ME (just look at my name, i KNOW)

Answer 8

the points on the jets are aerodynamic and the tubes as you call them. are external fuel tanks those provide extra fuel for the plane to go greater distances and those can be released by the pilot so basically they can be taken on and off

Answer 9

Drop tanks, Pitot head.

Answer 10

firstly the points at the front are for maximum aerodynamics, and those tubes are fuel tanks that can extend the range of the jet, and the pilots can drop them when they are empty.