0026 00
TM 1-1670-260-12&P
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3. RECOVERY FLIGHT PARAMETERS AND PRECAUTIONS
Flight parameters for the CH-47 recovery helicopter are specified in Table 1.
Table 1. Recovery Helicopter Flight Parameters
Maximum Airspeed:
40 Knots Indicated Air Speed (KIAS)
Maximum Bank Angle:
20 Degrees
Maximum Rate-of-Climb
500 Feet Per Minute (FPM)
Maximum Rate-of-Descent
1000 Feet Per Minute (FPM)
Drogue Chute
No
WARNING
Once the damaged helicopter is connected to the
recovery helicopter and lifted to a hover, the pitch
attitude of the damaged helicopter must be checked to
ensure a nose down attitude is achieved.
A damaged helicopter may rotate while in a hover.
This rotation may cause slings of some UMARK
rigging configurations to twist or to tighten at the main
rotor assembly. The rotation will generally stop as
airspeed is increased to approximately 5 to 10 knots.
The recovery helicopter flight crew should minimize
hover time.
If oscillations of damaged helicopter develop during
flight, tests have shown that lowering airspeed,
returning to wings level flight, and initiating a climb
has a stabilizing effect.
It is critical for the recovery helicopter flight crew to
report any unusual occurrences. For example, vertical
bounce, severe jerking of the damaged helicopter,
hard landing of the damaged helicopter following
recovery, UMARK component failure, or exceeding the
flight parameters. Report any unusual occurrences to
the unit responsible for the damaged helicopter.
Exceeding the flight parameters may severely damage
the main rotor assembly of the damaged helicopter,
requiring component replacement. Report the amount
and duration of any flight parameter exceeded to the
unit responsible for the damaged helicopter.
The height above ground level may be difficult to
determine during low-level UMARK operations due to
the length of the sling system. Flight crews should
exercise extreme caution during recovery operations
to ensure the damaged helicopter remains clear of
ground obstacles.
0026 00-2
