Questions for wise pilots

[flying free.LEVC]

I am a private pilot doing the entry exam for Londonmet (ATPL distance learning) and there are a couple of questions I never saw during my ppl training:

1. An aircraft is on ILS approach. The aircraft´s DME distance from the landing runway threshold is 10 NM. Assuming a 3 degree glide path, what would be the ground distance to be covered?

2. Incorrect fuel densities will increase or decrease the performance of the aircraft engine. Allowing for the same fuel type and volume, what would be the effect of using a fuel of SG 0.75 as apposed to the published ideal fuel of sg 0.8??

And the last one...

3. The fore and aft distance between the two main wheels and the single tail wheel of an aircraft is 8m. The unloaded weight of the aircraft is 20Kn and its centre of gravity is 0.5 behind the main wheels. Calculate the force on the tail wheel and on each main wheel.

I will appreciate any help with any of these question, I am stuck on them...I already finished the other 97 ¡¡ :D

[Poeli]

i'm not abpilot, but is the first one not just applying sinus and cosinus? You have a triangle with the angle being 3degrees. The 10nm is the (dont know the correct english term)the longest line of the triangle. If you take cos 3 *10nm you normally become the horizontal distance between the plane and the dme station/

[Da-20 monkey]

Well, question 2 is not so difficult. specific gravity is density/ density of water (1kg/m3). so the higher number is more dense, which gives the motor more oomph.
I leave q.3 to someone else.;)

[The500man]

1. An aircraft is on ILS approach. The aircraft´s DME distance from the landing runway threshold is 10 NM. Assuming a 3 degree glide path, what would be the ground distance to be covered?A. DME is measuring slant distance therefore the ground distance will be less than 10 NM.

2. Incorrect fuel densities will increase or decrease the performance of the aircraft engine. Allowing for the same fuel type and volume, what would be the effect of using a fuel of SG 0.75 as apposed to the published ideal fuel of sg 0.8??A. Decreased performance (less charge)

3. The fore and aft distance between the two main wheels and the single tail wheel of an aircraft is 8m. The unloaded weight of the aircraft is 20Kn and its centre of gravity is 0.5 behind the main wheels. Calculate the force on the tail wheel and on each main wheel.A. Tail wheel = 1.25 kN, main wheel = 9.375 kN.

20000 / 8 = 2500

Tail Wheel
2500 x 0.5 = 1250 N or 1.250 kN

Main Wheel
2500 x 7.5 = 18750
18750 / 2 (main wheels) = 9375 N or 9.375 kN

[Aviatorjoe]

To do the first question you would use . z = DO/DG * 60

z = Angle = 3 degrees
DO= Is the distance which you are off which is a variable, You gotta calculate that from phytagoras, find the DO, when you have the DG and angle(1 in 60 rule)
DG= 10 nm

Then rearrange the formula and wolla, you got the answer

[talkpedlar]

use the accepted rule of thumb.. 3 degree slope relates to 300'/mile

Ergo..10 miles = 3000'

You now have aircraft height and the length of the hypotenuse..apply formula!

Hope my reply is not CabSauv corrupted.

[mutt]

9.98 nautical miles :)

I wonder if Honeywell will provide a modification to our FMS that would make this sort of question meaningful :):)