Physics question using trig.?

Question

I need help with the following question as I cannot seem to get the correct answer with the formula.

A high-performance jet plane, practicing radar avoidance maneuvers, is in horizontal flight of h = 50 m above the level ground. Suddenly, the plane encounters terrain that slopes gently upward at 4.3°, an amount difficult to detect. How much time (in seconds) does the pilot have to make a correction to avoid flying into the ground? The speed of the plane is 1300 km/h.

Ok my first step here was to take the Tan(4.3) = 50m/Adjacent

This gave me an answer of 21.87372156 meters for the distance the plane travels before it would crash.

Then I took 1300km/h and converted to 1300,000 meters/3600 seconds = 361.1111111 meters/second.

Finally I took 21.87372156 meters / 361.1111111 = 0.0605733828 seconds before the plane crashes....

Apparently this is not the right answer but I cannot figure out why. Can anyone help?

Thanks

Answer 1

The triangle is 50m opposite, with an adjacent = ?,  angle 4.3 deg

Tan 4.3 = opp/adj to find adj rearrange to give

Adj = opp/tan 4.3 = 50 / 0.0752 = 665 metres to nearest metre

Time = distance / speed

convert km/h to m/s as you say 361.111 m/s

T = 665/361.11 = 1.84 seconds  

Answer 2

tan(4.3 deg) = opp / adj  = 50m / horiz dist

adjacent =horizdistance = 50m / tan(4.3)

= 50 /.07519   = 665 meter  <=== NOT 21.8 meteres

665m = 0.665km

time = dist / speed = 0.665 km / 1300 km /hr

= 5.115 * 10^(-4) hr

5.115 * 10^(-4) hr  * 3600 sec/hr = 1.814 sec