What is one bad thing about jet engines BESIDES pollution?

Question

This is for school.

Answer 1

Price

Answer 2

NOISE!  Many airports have noise restrictions in effect.

Answer 3

The only "bad" thing I can suggest about jet engines is that they don't give the chance for total combustion of fuel. This means ineffective utilization of fuel.

But then, it is something we gotta live with. The other benefits of the jet engine negates this minor setback.

Answer 4

I work on jet engines every day. The two biggest problems I see every day is the cost of parts, and the vulnerability to damage.

The average cost of an overhaul for the engine I work on is 3 to 5 million dollars. Some sample prices for you: One fan blade - $20,000 (there's 22 on my engine), The fan case - $600,000, One half inch fan bolt $150, One engine mount $250,000, One 8 inch long half inch diameter fuel tube - $8,000, One 20 ft. roll of fireproof tape used to wrap wire harnesses - $10,000.

There is nothing cheap in or on a jet engine.

While in flight the engine is very durable and unlikely to fail. Anything sucked in the front will most likely be swept to the outer end of the fan blades and go through the bypass air. However, during startup, if something is left inside or near the front of the engine it can cause major damage.

I've seen a small 5 cent screwdriver bit that was accidentally dropped in an engine cause over 5 million dollars in damage. I've seen pneumatic hoses from ground equipment tear the inside of an engine to pieces. And I've seen engines run into snowbanks that completey tore the fan apart.

I've seen engines that have sucked in some really large birds, but for the most part do nothing but smell bad. It's ground equipment and tools that do the most damage.

Answer 5

The only bad thing I know about jet engines is that your teacher wants you to make up something bad about them.

Jet engines are simple, reliable, economical to operate, easy to maintain and repair (if you've got the right equipment) and they are one of the least polluting types of technology in existence.

Jet engines are GOOD, not BAD.

Answer 6

they're loud.

they waste way too much fuel.

their fuel is very expensive.

the security checkpoints make it impossible to actually get on and off them...

why is someone who says they love planes asking for things that are bad about planes? =D

Answer 7

Only thing I can add, is that they don't spool up as fast as piston engines, so if you are really low and have the engine on idle, and need full power right away, it might take a few seconds before you get your wish.

However it is extremely seldom that this will cause any problem.

PS> noise is only a factor on older generation Jet engines.. new ones are very silent, and turbofans are not as inefficient at low altitudes as it might seem.

Answer 8

Jet engines are VERY inefficient at low altitudes.  (They suck great quantities of fuel even while just taxiing).  But they are great at high altitude where the air is thin and your true airspeed is high.  Jet operators just HATE to waste time on the ground with the engines running, or flying at low altitudes, (below about 15000 feet).  That is in comparison to piston engines which don't really use a lot of fuel while idling.

Answer 9

The only bad thing I can describe about turbine engines is their cost; very expensive. However, in terms of pure power, miles of travel produced, and their sheer reliability, I'd say the jet or turbine is a very good example of modern technology and the pollution is really not all that high for the benefit received.