Instrument Flight
Flight Procedures
Descent Comparison, no wind, 2,000 # FUEL: T-45C (all figures are approximate)
Fuel Flow (pph)
Airspeed (KIAS)
VSI (fpm)
DME to lose 1K
500 (idle)
250
-2,500
2
500 (idle), BDS
250
-6,000
1
500 (idle)
Max Range
-1,500
3-4
700 (75%)
250
-2,000
2.5
From cruise power and IAS at altitude, lower the nose to accelerate (if necessary) to desired descent
airspeed (usually 250 KIAS), then reduce power (if necessary) to maintain desired VSI. At altitude, you
will need to reduce fuel flow by approximately 50 pph for every -100 ft of VSI. You must request
permission to perform directed descents at rates less than 500 fpm.
Max Range Descent
Goal: Use less fuel while maximizing distance traveled. NATOPS lists the max range descent airspeed
and descent point in the BINGO tables for various airspeeds and configurations. Max range descent AOA
will be higher than the max range cruise AOA (triangle at 12-13 units). Center normally plans to descend
you at your altitude plus ten, so you may need to ask for an earlier descent. For example, the letdown
point for max range descent from FL350 is approximately 123 nm, but Center would not normally descend
you until 45 nm. A rough approximation is to let down three and one-half times altitude plus desired DME
from field level off.
Delayed Descent
Goal: Minimize downrange travel if your descent is delayed by ATC or weather. Use this strategy when
you are forced to stay higher than desired. At altitude, maintain max endurance AOA (“box” at 14 units)
until cleared lower, then lower the nose and accelerate to 250 KIAS, reduce power to idle and use boards
as necessary. The idle-with-boards configuration gives the maximum altitude loss for distance over the
ground.
All Descents
When descending through 5,000 ft AGL, call “platform” and comply with the “minute-to-live” rule. When
practical, retract the speed brakes.
STAR
A STAR is a preplanned instrument flight rule (IFR) air traffic control arrival procedure published for pilot
use in graphical and/or textual form. STARs provide transition from the enroute structure to an outer fix or
an instrument approach fix/arrival waypoint in the terminal area. Its purpose is to simplify clearance
delivery procedures.
Until the military fully distributes STAR publications, STARs will be issued to military pilots only when
requested in the flight plan or verbally by the pilot. Still, some of the “preferred” routes in the A/P-1A
contain STARs. Use of STARs requires pilot possession of at least the APPROVED textual description.
As with any ATC clearance or portion thereof, it is the responsibility of each pilot to accept or refuse an
issued STAR. Pilots should notify ATC if they do not wish to use a STAR by placing “NO STAR” in the
remarks section of the flight plan or by the less desirable method of orally stating the same to ATC. This
option may result in terminal delays and holding.
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