PART III - HANDLING
(b) On the climb
(i) High forward speeds at low altitudes may reduce
max. r.p.m. by as much as 100. This coupled with
the effect at (a) (i) may cause the r.p.m. at the
commencement of the climb to read as much as 150
less than the static ground figure. This condition
will disappear as the climb progresses.
(ii) Max. r.p.m. may also be reduced if the top temp.
controller comes into operation. On some engines
the temperature controller reaches the limit of its
control at altitudes above 40,000 ft. when climbing
at full throttle. It therefore becomes necessary to
close the throttle slightly to maintain j.p.t. below
685°C.
NOTE.- Until Mods. 372 and 438 are embodied, care
must be taken to ensure, by throttling back if
necessary, that at all altitudes the max. per-
missible j.p.t. is not exceeded.
(iii) During a climb at full throttle r.p.m. will increase
gradually but must not be allowed to exceed 8,100
r.p.m. When climbing at intermediate power it is
necessary to close the throttle gradually as altitude
is gained to maintain 7,800 r.p.m.
(c) In flight
(i) At intermediate throttle settings differing combina-
tions of airspeed and ambient air temp. may cause
the selected r.p.m. to vary. It will then be necessary
to adjust the throttle to maintain a constant figure.
(ii) With the throttle fully closed, the idling r.p.m.
increase with altitude and with increasing airspeed.
(iii) Negative G must not be applied for more than 15
secs.
(iv) It is recommended that movement of the throttle
should be smooth and progressive. However, rapid
throttle movements can be made at any altitude if
necessary, but the A.C.U. will automatically control
the rate of r.p.m. acceleration.
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