Technorati comments

nandakandamanda- pneumatic systems are usually only pressurized for a single use. Modern aircraft are usually equipped with a primary emergency landing gear extension system, but a large majority of aircraft now use gravity assisted systems; Meaning that as long as its possible to open the landing gear doors open gravity will actually cause the landing gear to extend and lock in place.

In my opinion the pilot should be applauded for his/her (it's 2011, folks!) control of the aircraft. Flying a large commercial aircraft on final approach involves a great deal of concentration, luckily the pilot was on their P's and Q's.

Finally, a topic I know something about!

As a licensed Aircraft mechanic with 10+ years of experience., I never thought I'd get a chance to comment on JT!

well, in NORMAL operation an aircraft's landing gear is lowered/raised using hydraulic power supplied by the aircraft's engine-mounted hydraulic pumps. In case of the failure of any of the associated pumps, tubing, valves all aircraft have back up systems, which usually consist of tanks of pressurized nitrogen which are used to "blow down" the landing gear, by pressurizing the residual fluid in the aircraft.