TM 55-1510-215-10
CHAPTER 7
PERFORMANCE DATA
Section I. INTRODUCTION
7-1. Description.
and other parameters relating to that phase of flight are
presented. In addition to the presented data, the pilot's
The charts presented in this chapter are based on
judgement  and  experience  will  be  necessary  to
and are consistent with the recommended operating
accurately obtain performance under a given set of
procedures and techniques set forth in other chapters of
circumstances.  The conditions for the data are listed
this manual. The charts contain the performance data
under the title of each chart.  The effects of different
necessary for preflight and in-flight mission planning.
conditions are discussed in the text accompanying each
Explanatory text applicable to each type of chart is
phase of performance.
Where practical, data are
included to illustrate the use of the data presented.
presented at conservative conditions.  However, NO
GENERAL CONSERVATISM HAS BEEN APPLIED.
7-2. Purpose.
WARNING
a. The purpose of this chapter is to provide the
best available performance data for the U-21G aircraft.
Regular use of this information will enable the pilot to
Exceeding  operating  limits  may
receive maximum safe utilization from the aircraft.
cause permanent damage to critical
Although maximum performance is not always required,
components. Overlimit operation can
regular use of this chapter is recommended for the
decrease
performance,
cause
following reasons:
immediate failure, or failure on a
subsequent flight.
(1) Knowledge of performance margin will
allow  the  pilot  to  make  better  decisions  when
7-4. Limits.
unexpected  conditions  or  alternate  missions  are
encountered.
Applicable limits are shown on the charts as red
lines.
Performance  generally  deteriorates  rapidly
(2) Situations
requiring
maximum
beyond limits.  If limits are exceeded, minimize the
performance will be more readily recognized.
amount and time. Enter the maximum value and time
above  limits  on  DA  Form  2408-13  so  proper
(3) Familiarity  with  the  data  will  allow
maintenance action can be taken.
performance to be computed more easily and quickly.
7-5. Chart Explanation.
(4) Experience will be.  gained in accurately
estimating the effects of variables for which data are not
A complete series of performance charts are
presented.
provided for U-21G aircraft in this manual. These charts
furnish the pilot with sufficient data to make an intelligent
b. The information is primarily intended for mission
and safe flight plan. The charts include data on takeoff,
planning and is most useful when planning operations in
climb, landing, and operating instructions for cruising
unfamiliar areas or at extreme conditions. The data may
flight from maximum endurance to normal rated power.
also be used in flight, to establish unit or area standing
No allowance has been made for navigational error,
operating
procedures,
and
to
inform
ground
formation flight, or other contingencies.  Appropriate
commanders of performance/risk tradeoffs.
allowances for these items should be dictated by local
regulations and should be accounted for when the fuel
7-3. General.
available for cruise is determined.  The charts are
arranged to give maximum facility of use in preflight and
The data pr esented shall cover the maximum range
in-flight planning.  All charts are based on free air
of conditions and performance that can reasonably be
temperature (FAT) conditions and pressure altitude.
expected. In each area of performance, the effects of
altitude, temperature, gross weight, and gross weight,
7-1