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Purpose Of DC-8 Air Scoops?

Sat Mar 23, 2002 6:18 pm

Simple question.

I'm sure there's a simple answer.
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RE: Purpose Of DC-8 Air Scoops?

Sat Mar 23, 2002 6:19 pm

Im no expert but i beleive they are meant for cooling the avionics.
Once you have tasted flight, you will walk the earth with your eyes turned skyward; for there you long to return
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RE: Purpose Of DC-8 Air Scoops?

Sat Mar 23, 2002 8:36 pm

The purpose of the scoops on the nose of the DC8, are they are air inlet scoops for the air cycle machines, which are in the nose. These are the old versions of air conditioning packs hope this helps.
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Sat Mar 23, 2002 10:05 pm

These are the inlets for the CTC's (Cabin Turbo Compressors), there are four installed on the DC-8 models. They turn at about 35,000 RPM and are used for pressurization. The four switches are located on the Flight Engineers panel with a gauge to view RPM. Under each switch is an overspeed button to simulate an overspeed condition, without overspeed protection circuitry, the CTC would grenade the turbine.

Number 1/2 are paired and 3/4 are paired, meaning they intersect each other with a check valve. Sometimes the check valve would break and the other CTC could run backwards, a common logbook write up.

Those scoops are also heated and the scoops anti-ice switch, located on the overhead panel, energizes the system.