Because the
question gives the factored runway length we can go into the right side of the
graph with the given distance, 2000ft, and into the left side of the graph with
the stated conditions of ISA and 4000ft. Where the two lines meet (make sure
you put the wind component in) we'll get the take-off mass.
Because you've been given the factored runway length that weight will comply
with the regulatory requirements. The actual runway length is 2000 x 1.15 =
2300ft.
So we'll be getting airborne in 2000ft and the additional 300ft is the safety
factor.
When considering any of these type of questions look for the word required
If it says calculate the landing distance required
or take-off distance required then we have to use the appropriate safety
factor.
One sentence of caution....the MRJT1 graphs already have the regulatory factors
built in, so the application only applies to the SEP and MEP graphs.