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gravery · Joined: 15 Oct 2004 Posts: 13 Location: Le Chesnay, France

I was told some years ago that emergency descent procedure on the Constellation implied using the reverse on the two inboard engines... Any expert or former Constellation crew member could confirm ?

kmccutcheon · Posted: Wed Jan 13, 2016 07:11 Post subject:

I have reviewed flight manuals for Lockheed 649, 749, 1049H, C-121C & G, and RC-121D. The latest of these (RC-121D) was publish in 1958. None make any mention of the technique you describe for rapid descents. All state that the most rapid descent rate is achieved in the clean configuration at Vne with superchargers in LOW setting, propellers at 2,600 rpm, and throttles closed.
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Kimble D. McCutcheon

gravery · Joined: 15 Oct 2004 Posts: 13 Location: Le Chesnay, France

Thanks Kimble.
I just got the flying report of an Air France L1049 in 1966. The A/C was back from overhaul and test flown (no passengers and only the needed fuel). They performed various tests at FL250 and the last one was an emergency descent to FL50. They don't indicate the descent rate but describe the procedure using reverse on both inboard engines, keeping power available on the other two (reverse to low pitch took 15 sec).
Airlines own procedures maybe ?

kmccutcheon · Posted: Wed Jan 13, 2016 08:46 Post subject:

Was it the descent from FL250 to FL50 that took 15 sec or the change to reverse pitch?

It is true that airlines developed their own procedures. Unfortunately, I do not have access to any airline manuals covering Constellation operations.
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Kimble D. McCutcheon

gravery · Joined: 15 Oct 2004 Posts: 13 Location: Le Chesnay, France

Switching from reverse to low pitch took 15 sec.

rwahlgren · Joined: 15 Aug 2003 Posts: 324

kmccutcheon · Posted: Sat Jan 16, 2016 06:57 Post subject:

akambic · Joined: 09 Feb 2014 Posts: 10 Location: Fairfax, Virginia

Spoke with an old friend who has over 5000 hours on USAF Connie's from the late 1960s and early 1970s. He said he has never heard of this procedure. He stated that they never reversed props in flight.

He recalls hearing about DC-8s employing Reverse Idle on inboard engines for descents.

Tony

wlewis · Joined: 04 Feb 2006 Posts: 9 Location: culver city, ca

Like others I have numerous 049 to 1049 manuals, mainly flight, CAA approved published by Lockheed + TWA published, nothing about reversing in flight in CAA (FAA now) approved manuals. TWA Flight Manual for 749 model connie.

"under no conditions attempt reverse pitch operation in flight" after procedure on unlocking / overriding safety switches (squat switches) on landing gear scissors. So reverse in flight was possible!!

Using reverse thrust for ground backing-up OK just needed guide man @ wing tips and observing CHT as per TWA manual!

rwahlgren · Joined: 15 Aug 2003 Posts: 324

Any use of propeller reverse, will cause a lack of cooling airflow to the engine.
edited it to make more sense.

jschauer · Joined: 19 May 2004 Posts: 93 Location: Justin, Texas

Way back in A&P school we watched a movie of the "new" DC-4(6) with propeller reversing. One scene was a DC-4(6) that reversed its props in flight and had a very steep descent.