destination airport as variables to find the fuel, time and distance
values from the graph (Figure 5-31). Now, subtract the values
obtained from the field conditions from the values obtained from
the cruise conditions to find the true fuel, time and distance values
needed for the flight plan.
The values obtained by proper utilization of the graphs for the
descent segment of our example are shown below.
(1) Time to Descend
(3.5 min. minus 1 min.) 2.5 min.*
(2) Distance to Descend
(7 miles minus 2 miles) 5 miles*
(3) Fuel to Descend
(.25 gal. minus .1 gal.) .15 gal.*
(e) Cruise
Using the total distance to be traveled during the flight, subtract
the previously calculated distance to climb and distance to descend to
establish the total cruise distance. Refer to Figure 5-17 when
selecting the cruise power setting. The established pressure altitude
and temperature values and the selected cruise power should now be
utilized to determine the true airspeed from the Speed Power graph
(Figures 5-19 or 5-21).
Calculate the cruise fuel flow for the cruise power setting from
the information provided in Figures 5-19 or 5-21.
The cruise time is found by dividing the cruise distance by the
cruise speed, and the cruise fuel is found by multiplying the cruise
fuel flow by the cruise time.
The cruise calculations established for the cruise segments of
the flight planning example are as follows:
(1) Total Distance 300 miles
(2) Cruise Distance
(e)(1) minus (c)(4) minus (d)(2),
(300 miles minus 4 miles minus
5 miles) 291 miles
(3) Cruise Power, Best Economy
Mixture 65% rated power
*reference Figure 5-31
SECTION 5 PIPER AIRCRAFT CORPORATION
PERFORMANCE PA-38-112, TOMAHAWK
REPORT: 2126 ISSUED: JANUARY 20, 1978
5-6 REVISED: MAY 10, 1982
destination airport as variables to find the fuel, time and distance
values from the graph (Figure 5-31). Now, subtract the values
obtained from the field conditions from the values obtained from
the cruise conditions to find the true fuel, time and distance values
needed for the flight plan.
The values obtained by proper utilization of the graphs for the
descent segment of our example are shown below.
(1) Time to Descend
(3.5 min. minus 1 min.) 2.5 min.*
(2) Distance to Descend
(7 miles minus 2 miles) 5 miles*
(3) Fuel to Descend
(.25 gal. minus .1 gal.) .15 gal.*
(e) Cruise
Using the total distance to be traveled during the flight, subtract
the previously calculated distance to climb and distance to descend to
establish the total cruise distance. Refer to Figure 5-17 when
selecting the cruise power setting. The established pressure altitude
and temperature values and the selected cruise power should now be
utilized to determine the true airspeed from the Speed Power graph
(Figures 5-19 or 5-21).
Calculate the cruise fuel flow for the cruise power setting from
the information provided in Figures 5-19 or 5-21.
The cruise time is found by dividing the cruise distance by the
cruise speed, and the cruise fuel is found by multiplying the cruise
fuel flow by the cruise time.
The cruise calculations established for the cruise segments of
the flight planning example are as follows:
(1) Total Distance 300 miles
(2) Cruise Distance
(e)(1) minus (c)(4) minus (d)(2),
(300 miles minus 4 miles minus
5 miles) 291 miles
(3) Cruise Power, Best Economy
Mixture 65% rated power
*reference Figure 5-31
SECTION 5 PIPER AIRCRAFT CORPORATION
PERFORMANCE PA-38-112, TOMAHAWK
REPORT: 2126 ISSUED: JANUARY 20, 1978
5-6 REVISED: MAY 10, 1982
To Next Page
Loading...
