Old "Props" and Long Sectors
Thread Starter
Old "Props" and Long Sectors
Folks,
I read elsewhere of a regular US-Far East non-stop of 17 hours.
I seem to recall that, in the brief, pre-jet period of L1649/DC7C "front line" operation on the North Atlantic, that non-stops of over twenty hours were not uncommon, these "ultimate recips." having exceptional range, but not speed.
Did I read that a particular US West Coast-Paris flight was almost 24 hours? TWA and a Super Constellation?
I'd be fascinated to hear what crew, technical and "passenger comfort" issues were raised by these largely-forgotten "long hauls".
r
I read elsewhere of a regular US-Far East non-stop of 17 hours.
I seem to recall that, in the brief, pre-jet period of L1649/DC7C "front line" operation on the North Atlantic, that non-stops of over twenty hours were not uncommon, these "ultimate recips." having exceptional range, but not speed.
Did I read that a particular US West Coast-Paris flight was almost 24 hours? TWA and a Super Constellation?
I'd be fascinated to hear what crew, technical and "passenger comfort" issues were raised by these largely-forgotten "long hauls".
r
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Certainly not the longest sectors but must count as the longest scheduled journeys of the time were the flights performed by Pan Am’s China Clippers. San Francisco to Manila in 6 days with nearly 60 hrs flying time stopping at Honolulu, Midway, Guam; if nothing else a great feat of navigation.
A Runyonesque Character
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1958 Summer schedule
TW751 L-1649 dep PAR 2100 arr SFO 1055 = 21h55m
PA127 DC7C dep PAR 2359 arr LAX 1355 = 21h55m
About 2hr quicker Eastbound.
PA127 DC7C dep PAR 2359 arr LAX 1355 = 21h55m
About 2hr quicker Eastbound.
Thread Starter
Thanks.
And no film or multi-channel IFE, just a days' worth of Wright Turbo Compunds (providing they kept going)
I understand that that power plant was famous for it's particularly long exhaust flame...
r
And no film or multi-channel IFE, just a days' worth of Wright Turbo Compunds (providing they kept going)
I understand that that power plant was famous for it's particularly long exhaust flame...
r
These days long overwater flights are routinely operated by 4, 3 and with ETOPS rules, 2 engined jet aircraft. In the days of piston props over the ocean however, what regulatory restrictions were placed on the above flights in terms of sector times, engine reliability, diversion airfields, crew duty hours, etc?
Thread Starter
...and, of course, no INS...
When SAS started their trans-polar flights with DC7-Cs, they were right on the edge of aeronautical navigational skills, so I understand. The precise details escape me, but I seem to recall special grid-map charts and difficulties in using celestial navigation.
r
When SAS started their trans-polar flights with DC7-Cs, they were right on the edge of aeronautical navigational skills, so I understand. The precise details escape me, but I seem to recall special grid-map charts and difficulties in using celestial navigation.
r
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Astro navigation is suitable for high latitude flying, and yes, grid nav was used, as the compass is not all that reliable.
As for aircraft restrictions, all were four engine types, and the only problem (other than excessive oil consumption) was descending if a powerplant failed (driftdown) or a pressurisation failure.
In addition, all cargo compartments had to be either class C or D.
Longer flights carried two crews.
As for aircraft restrictions, all were four engine types, and the only problem (other than excessive oil consumption) was descending if a powerplant failed (driftdown) or a pressurisation failure.
In addition, all cargo compartments had to be either class C or D.
Longer flights carried two crews.
I guess it would have stepped up as fuel was burnt. Probably starting around FL170 and ending up around the FL210-230 mark. I remember cruising at around FL210 on SABENA DC-7s between Brussels and Madrid, but that wasn't a heavy oceanic flight of course.
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Long ago...
Yes, sometimes enroute fuel stops were made, however, the record for non-stop piston ops was a TWA 1649A-98 Constellation, ORY-SFO.
Time enroute, nonstop....23 hours 10 minutes.
Keep in mind that this aircraft type, which yours truly has flown previously, was fitted with a fuselage oil tank, from which each engine's oil tank could be replentished.
In addition, it carried 9,835 US gallons of 115/145 aviation gasoline, which was also a record for a civil piston type.
It cruised at 315 KTAS, consumed 390 USGallons of fuel/hr...and if you were lucky, did not run out of oil prior to the destination.
It had a port in the fuselage top for astro navigation, and these long range flights absolutely carried a Navigator, who was truly proficient at pressure pattern navigation...which ain't easy, at least from my perspective.
My personal record in this rather unique aeroplane, 16 hours, 42 minutes, HNL-TPE.
Cruising levels.
A heavy 1649 Constellation or DC-7C would normally not get above 14,000 feet initially, for the first two hours.
As weight decreased, the aircraft could then climb higher.
Blowers (engine superchargers) were shifted to high at 13,000 feet, and a long oceanic flight would end up at flight level 210/220 eventually.
It should be noted that with these piston engine airliners, fuel consumption did not normally decrease with altitude however, the true airspeed DID increase.
These engines were always cruised at a constant power setting, usually on the order of 45 to 50% BHP, using the lowest suitable RPM.
Engine mixtures were set to auto-lean, and BMEP power recovery was used, to enhance lean of peak operation.
Time enroute, nonstop....23 hours 10 minutes.
Keep in mind that this aircraft type, which yours truly has flown previously, was fitted with a fuselage oil tank, from which each engine's oil tank could be replentished.
In addition, it carried 9,835 US gallons of 115/145 aviation gasoline, which was also a record for a civil piston type.
It cruised at 315 KTAS, consumed 390 USGallons of fuel/hr...and if you were lucky, did not run out of oil prior to the destination.
It had a port in the fuselage top for astro navigation, and these long range flights absolutely carried a Navigator, who was truly proficient at pressure pattern navigation...which ain't easy, at least from my perspective.
My personal record in this rather unique aeroplane, 16 hours, 42 minutes, HNL-TPE.
Cruising levels.
A heavy 1649 Constellation or DC-7C would normally not get above 14,000 feet initially, for the first two hours.
As weight decreased, the aircraft could then climb higher.
Blowers (engine superchargers) were shifted to high at 13,000 feet, and a long oceanic flight would end up at flight level 210/220 eventually.
It should be noted that with these piston engine airliners, fuel consumption did not normally decrease with altitude however, the true airspeed DID increase.
These engines were always cruised at a constant power setting, usually on the order of 45 to 50% BHP, using the lowest suitable RPM.
Engine mixtures were set to auto-lean, and BMEP power recovery was used, to enhance lean of peak operation.
Last edited by 411A; 6th Apr 2007 at 06:45.
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Beautiful Youtube footage of the Breitling connie
Something to set the mood as you read through these posts:
http://www.youtube.com/watch?v=Llsk7tqbjhw
http://www.youtube.com/watch?v=Llsk7tqbjhw
I too have understood that these 20-hour nonstop schedules from Europe to California actually featured an unadvertised refuelling stop, not shown in the timetable, at Winnipeg. The SAS DC-7C from Copenhagen to Seattle would stop at Sondrestrom in Greenland.
Regarding the SAS trans-polar flights which were pioneers on those routings, the problem that had to be overcome was that at certain times of the year, with no other radio navaids available, celestial navigation at high latitude at certain times of the year was not posible because the sun stayed just below the horizon for many hours, out of sight, but the sky was still bright enough that stars were not visible. There was a patented optical instrument developed which finally overcame this problem and allowed the flights to start, seemingly by allowing an accurate interpolation of the sun's position beneath the horizon. I bet close proximity to magnetic north also compounded any discrepancies. There was detail about it all in a Propliner article on the SAS DC-7C trans-polar operation some years ago, sorry I don't have the time to go through all the back issues.
Regarding the SAS trans-polar flights which were pioneers on those routings, the problem that had to be overcome was that at certain times of the year, with no other radio navaids available, celestial navigation at high latitude at certain times of the year was not posible because the sun stayed just below the horizon for many hours, out of sight, but the sky was still bright enough that stars were not visible. There was a patented optical instrument developed which finally overcame this problem and allowed the flights to start, seemingly by allowing an accurate interpolation of the sun's position beneath the horizon. I bet close proximity to magnetic north also compounded any discrepancies. There was detail about it all in a Propliner article on the SAS DC-7C trans-polar operation some years ago, sorry I don't have the time to go through all the back issues.
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Regarding high latitude navigation. With two gyro compasses fitted there is no problem with polar flying. Gyro compass drift rates are montoired alternately during the north bound leg until passing 80 N when the magnetic coupling to both is switched off. The gyros are then corrected for the recorded drift rate every fifteen minutes until passing 80 N southbound again. RAF Britannias used the method on the aero-systems training courses well into the 1970s.
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As of now, the FAR 121.161 reads
So, 3 engine piston props were forbidden from long flights (But the wording of rule suggests that turbine-powered turboprops with 3 engines are allowed long flights... the only turboprop trimotor is Trislander, and does it have range for 2 hours?).
No language forbids 6 engine piston powered planes, but though B-36 was mass produced and XC-99 flew, Convair 37 did not enter service.
Now, Boeing 377 was not required to survive 2 engines out of 4. There was a famous incident where a 377 did lose 2 engines on crossing to Hawaii. It remained airborne, but with increased fuel burn, they had no hope of reaching land. What they did was find out by radio that there was a coast guard ship somewhere in the middle of ocean, then they flew there and I think burned off some more fuel, and ditched in midocean. The fuselage broke apart on ditching; but the captain had feared it would happen, and moved passengers so they all stayed in one piece and unhurt. Then they were picked up by the ship with no injuries.
As for passenger comfort, some propliners featured lower and upper sleeping berths.
no certificate holder may operate two-engine or
three-engine airplanes (except a three-engine turbine powered airplane)
over a route that contains a point farther than 1 hour flying time (in
still air at normal cruising speed with one engine inoperative) from an
adequate airport.
three-engine airplanes (except a three-engine turbine powered airplane)
over a route that contains a point farther than 1 hour flying time (in
still air at normal cruising speed with one engine inoperative) from an
adequate airport.
No language forbids 6 engine piston powered planes, but though B-36 was mass produced and XC-99 flew, Convair 37 did not enter service.
Now, Boeing 377 was not required to survive 2 engines out of 4. There was a famous incident where a 377 did lose 2 engines on crossing to Hawaii. It remained airborne, but with increased fuel burn, they had no hope of reaching land. What they did was find out by radio that there was a coast guard ship somewhere in the middle of ocean, then they flew there and I think burned off some more fuel, and ditched in midocean. The fuselage broke apart on ditching; but the captain had feared it would happen, and moved passengers so they all stayed in one piece and unhurt. Then they were picked up by the ship with no injuries.
As for passenger comfort, some propliners featured lower and upper sleeping berths.
The Trislander is a piston-engined aircraft; I cannot recall any three-engined turboprops at all.
The French Latecoere 631 flying boat had 6 (P&W R2800) engines.
That ditching is spectacular. They were fortunate that it was calm. I wonder if the skipper was ex-Pan Am flying boats, could well have been.
The French Latecoere 631 flying boat had 6 (P&W R2800) engines.
That ditching is spectacular. They were fortunate that it was calm. I wonder if the skipper was ex-Pan Am flying boats, could well have been.
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I can think of but one WHBM - the Tri-Turbo-Three, Jack Conroy's much-modded DC-3 which turned up at Farnborough one year. 
(Thanks to Goleta Air and Sapce Museums excellent website!)
(Thanks to Goleta Air and Sapce Museums excellent website!)
