power out flight

RE: power out flight

http://www.keymags.co.uk/dcforum/DCForumID3/2138.html

wrong1 – use above!!

RE: power out flight

Yea n/p m8 – if u ever want anything i can help u with and to save u time just e-mail me from above and i’l do my best for ya.

http://www.keymags.co.uk/cgi-bin/dcforum/dcboard.cgi?az=read_count&om=2…

and theres the link 4 ya

RE: power out flight

EGNM- I dont own a computer and am constrained to very little time in internet cafes so unfortunately I am unable to research all the post in this forum for info on airliner glide ratios. If you could post the name of the thread you mentioned Id very much appreciate it.
Concerning jet airliner glide ratios, I am very, very surprised to hear that they can reach 15/1 much less 20/1 not only because of engine drag, but because airliners have high wing loadings to operate efficiently. Infact were it not for the flaps and leaning edge surfaces on airliners, they could hardly get off the ground. This flaps not only dramitaclly change wing camber but even increase wing area. Also Im familiar with motorgliders that use feathered props, I recall one where the glide ratio is only around 18/1 when set for powered flight, but jumps to its full potencial of 30/1 when feathered. So one can only imagine how much drag the many rows of large fans on an airliner would cause. I respect peoples professional opinion here, its just so surprising that airliners have glide ratios equal to purpose built gliders like the schwiezer 2-33. Would anyone off hand know the best glide ratio of the dash-8 series of turboprop commuter airliners are?

RE: power out flight

[updated:LAST EDITED ON 15-10-02 AT 10:01 AM (GMT)]The big fans actually produce surprisingly little drag as most of the airflow passes straight through them. The TriStar L/D was as high as 20:1

RE: power out flight

Mixtec – we had a conversation on this subject a few weeks bak if u look thru the records you will find it. For your infomation SOFTLAD is a cabin crew member on board MYT a/c and Wyswig is a B757-200 f/o for JMC – so these r ppl who kno their stuff

RE: power out flight

“A B757-200 would glide around 120nm if it was at 37’000 ft and lost both engines.”

SOFTLAND-By those figures,the B757 would have a glide ratio of around 1/15. I find it hard to believe that the enormous drag of the large turbofan engines would allow such a high glide ratio.

RE: power out flight

The distance any aircraft is capable of gliding is ruled by its height above ground, or sea, its speed, its glide ratio(and thus its glide angle), its weight and the prevailing weather conditions. Its speed and weight are combined to help arrive at the aircrafts glide ratio.

Every aircraft has a glide ratio, and it is best represented by the right-angled triangle. The vertical edge denotes the height above ground, and the hypotenuse represents the distance the aircraft covers. The glide angle changes the angle of the hypoteneuse, between o(!) and 90 degrees. For example, 90 degrees equals a glide angle of 0! or STRAIGHT DOWN. Some gliders (the stemme S10 for example) have glide ratio’s of 1:50. so for every vertical unit of measure travelled downwards, 50 units of measure are travelled forwards.

In simple terms the glide ratio depends on the L/D of the aircraft. This is a definite term for each aircraft.

the speed required to maintain minumum lift requires the aircraft to achieve a certain nose down angle, and thus descent rate. The heavier the aircraft the greater speed required.

this is affected by the prevailing weather(is this aircraft flying into the wind??) and the height of the aircraft(glide farther if you are higher up) I have heard that one aircraft managed to ‘glide’ 60 odd miles to reach the nearest airfield, after running out of fuel.

coanda

RE: power out flight

In the event of dual engine failure in a twin, a RAT (Ram Air Turbine) drops down which will provide hydraulic pressure for one of the aircraft hydraulic systems. This gives you limited flight controls.

RE: power out flight

A B757-200 would glide around 120nm if it was at 37’000 ft and lost both engines.

Regards,

Lyndon.