View Full Version : Old "Props" and Long Sectors

Midland 331
1st Apr 2007, 18:59

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".


1st Apr 2007, 21:27
Can I also mention the wartime QANTAS Catalina service from Ceylon to Perth.This often involved over 30 hours in the air at 127mph.

2nd Apr 2007, 07:44
Certainly not the longest sectors but must count as the longest scheduled journeys of the time were the flights performed by Pan Amís 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.

2nd Apr 2007, 11:59
TW751 L-1649 dep PAR 2100 arr SFO 1055 = 21h55m
PA127 DC7C dep PAR 2359 arr LAX 1355 = 21h55m

About 2hr quicker Eastbound.

Midland 331
2nd Apr 2007, 12:30

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...


3rd Apr 2007, 02:58
That exhaust flame got REALLY long when a PRT went TU....:ooh: :ooh:
About twenty feet long, or more.
An interesting sight.

3rd Apr 2007, 11:04
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?

Midland 331
3rd Apr 2007, 11:55
...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.


4th Apr 2007, 01:25
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.

5th Apr 2007, 16:12
The SSK, You may well be right but I'm not entirely sure that these ORY-LAX flights were truly non-stop. A scheduled fuel stop did not always feature in timetables.

The AvgasDinosaur
5th Apr 2007, 16:32
Could someone please advise me on the normal cruising levels used on these flights, eastbound and westbound.
Thanks in anticipation
Be lucky

5th Apr 2007, 20:47
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.

6th Apr 2007, 06:35
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.

7th Apr 2007, 08:56
Something to set the mood as you read through these posts:


:D :D :)

8th Apr 2007, 00:20
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.

9th Apr 2007, 01:17
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.

11th Apr 2007, 16:55
As of now, the FAR 121.161 reads

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.

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.

11th Apr 2007, 18:07
This the one?

11th Apr 2007, 20:19
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.

11th Apr 2007, 22:31
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!)

12th Apr 2007, 01:12
Well, now, that Coast Guard ship that the PanAmerican Stratocruiser just 'happened to find' was, in fact, Ocean Station November, which steamed in a grid pattern at 30N 140W for many many years.
(Not always the same ship, of course, it was changed out every eight weeks).
It had a 1KW NDB on board (360kc) and provided unsurpassed navigational aid for over 800 miles.
Flown over it many times with DC-6B and 1649 Constellation aircraft.
Ah, the good 'ole days.:ok:
The concerned PanAm B377 was very unlucky.
A propeller overspeed which required the fire handle to be pulled (failed prop feather oil line) to seize the engine and...a General Electric turbocharger failure on another engine.
Just not their day.:{

Footless Halls
12th Apr 2007, 18:18
In the '50's, my father used to fly as a passenger in Pan Am Stratocruisers crossing the Pacific service periodically. He told that on one he met a Stewardess who had been on a previous flight which had ditched successfully without losing a single life. My recollection is that she had said this was after a total engine failure and that the aircraft had glided down to its ditching. Pehaps I'm wrong - maybe she was on this flight. (Was there ANOTHER Stratocruiser ditrching which involved total engine failure and resulted in no casualties?)

I recall he asked her what the most frightening bit, and she'd said: "waiting during the descent; it took 20 minutes".

Sitting in the Stratocruiser's successor more recently, as a guest of Sir Richard or of BA, I've often wondered whether it would be possible to ditch a 747?

12th Apr 2007, 19:21
There was another Boeing 377 Stratocruiser lost that year when it ditched but not due to engine failure.

On the 2nd April 1956 Northwest Flight 2 (Seattle-Portland-Chicago-New York) took off from Seattle at 08:06. As the aircraft reached 2000 feet, at 145 knots airspeed, the flaps were retracted. Severe buffeting started and the aircraft tended to roll to the left. Thinking it was an asymmetric flap condition, the captain reduced power to stop the buffeting, but of no avail. Full power was applied again and plans were made to divert to McChord AFB. The plane continued to lose altitude and was not able to reach McChord. A ditching was carried out in Puget Sound. The aircraft sank 15 minutes after the ditching. It appeared that the aircraft had taken off with the engine cowl flaps fully open.

All 38 on board escaped from the aircraft but 5 people died in the cold water before being picked up.

12th Apr 2007, 20:22
There's a brief report here (http://www.planecrashinfo.com/1956/1956-17.htm).

2nd May 2007, 21:13
At last! something to contribute :8

Back around 1985 I lived with a young lady in Santa Barbara and I took a temporary job at the airport (actually in Goleta) with Tracor (?) doing document control on a conversion of United's DC10s. They were putting the galley upstairs AND adding extra seats :*

I remember seing this aircraft sitting on the ramp with the cockpit burned out. The sadness I felt at seeing this was soon eclipsed by the sadness I felt when the delightful J******r poilitely told me I had exceeded my operational lifespan. :{


I'm still in touch with her friend though :E

3rd May 2007, 00:48
That's the John Conroy Tri-Turbo 3 version of the DC-3, with 3 P&W PT-6 engines in place of the 2 P&W R1830's pistons. I think there was only one of them ever converted to 3 engines. I know it was flown on skis in the Arctic somewhere, Alaska maybe. Before this attempt, Conroy had converted another DC-3 to RR 500 series Darts. It wasn't a commercial success either. There's a firm in Oshkosh WI, Basler, that does do a great freighter conversion of the DC-3 with 2 PT-6's. They install a fuselage plug to increase the cargo capacity.

3rd May 2007, 08:04
Conroy had converted another DC-3 to RR 500 series Darts. It wasn't a commercial success either.
BEA converted two DC-3s in the early 1950s to RR Dart turboprops. They used them for operational experience of turbine operation, as freighters, before the Viscount came into service. Must have been one of the earliest commercial turbine operations in the world, it went on for quite some time.

* See below.

3rd May 2007, 15:53
Having been in South Africa a few years ago I was surprised to find not one but several DC-3's with Dart engines, so someone must have liked 'em....:}

3rd May 2007, 18:07
Sure they were Darts 411A, I know some of the Basler PT-6 conversions ended up out there (in the last decade or two)? The SAAF liked their Daks!

3rd May 2007, 18:53
"Can I also mention the wartime QANTAS Catalina service from Ceylon to Perth.This often involved over 30 hours in the air at 127mph." - Renfrew

G'day Chaps

Quantas Empire Airways commenced flying boat service between Ceylon and Western Australia in July 1943. The route flown four times-weekly, was 3, 523 miles long making it at the time the longest non-stop trans-ocean flight in the world. If it had not been for the fact that the Cocos Islands were a possible target of attack by the Japanese, the service may never have been implemented.

The Consolidated Catalinas were fitted with special fuel and oil tanks at the corporation's workshops in the U.K. Marine Base.

Quantas Empire Airways supplemented the route later on with the use of the Consolidated Liberator which linked up with Tasman Empire Airways.

Avro Lancastrians flew a high-speed mail run (including a limited number of pax) from the United Kingdom to New Zealand during the latter stages of the war. The time enroute was 86 hous and at the time was the longest civil air route in the world.


3rd May 2007, 21:21
Passengers on the Perth - Ceylon PBY flights were given a membership in the "Order of the Double Sunrise" because the sun rose twice during the time it took to complete the flight. :p

In the interest of accuracy, allow me to rephrase my statement about the commercial success of the Dart powered DC-3.

Of the more than 10,000 examples of the DC-3/C-47 that were produced, a handful were converted to RR Dart turboprops. This seems to indicate the conversion was less than a resounding success. :p

3rd May 2007, 23:49
No doubt about it, treadigraph, you can't miss the whine at 'round about 11,000 RPM, or slightly lower.

Quick, cover 'yer ears, the Darts are a commin'...:\

Brian Abraham
4th May 2007, 01:58
The British, forget which airline (BEA?), converted a few DC-3's to Darts to gain experience with their operation prior to the introduction of the Viscounts.

4th May 2007, 07:17
BEA Dart Dakotas

The two BEA turboprop DC3s were G-ALXN and G-AMDB which were converted in 1951, being paid for by the government as part of their development support for the Viscount and the Dart. Field Aircraft at Tollerton did the work, which took much of 1951. They tended to operate cruising at 25,000 feet so the crew must have been on oxygen. A range of technical issues arose (it was principally a development project) with engine icing (ever the bugbear of early turboprops) and the water-methanol system. They were converted back at the end of 1953.

4th May 2007, 07:50
The Dart certainly posseses a distinctive note but I'll venture that it is not as pleassing to the ear as radials...! :ok:

4th May 2007, 16:25
This is quite true, treadigraph, the Darts are screamers alright on the ground, but OK in flight.
However, having said this, the radials I flew were always a delight.

Most reliable, Pratt&Whitney R-2800CB16 (DC-6B).

Most fuel efficient, CurtisWright 3350 turbocompound series (L1649).

Smoothest....P&W R-4360's.

The latter were almost turbine-like, and of course, were fitted to the Stratocruiser, which I flew for only a short time.
All too short, actually, now that I think about it.

The jets simply are not in the same class...a bygone era where it was an adventure to fly.

4th May 2007, 17:13
Having been in South Africa a few years ago I was surprised to find not one but several DC-3's with Dart engines,It is with some trepidation that I suggest you are mistaken :ouch:
I'm with treadigraph, the SA goonies were undoubtedly Basler (PT6) conversions. AFAIK there were but 4 Dart-powered ones: an RAF Dakota in 1947, the two aforementioned BEA ones and Jack Conroy's N4700C. There was also a Mamba-powered one (RAF) which was restored to PWs and demobbed. I don't have the RAF serials, but I'm sure they will be instantly forthcoming....

Edited to add: also N156WC, but that was a C-117/R4D-8.

4th May 2007, 17:46
Smoothest....P&W R-4360's.
Apart from when they were :

a) Backfiring.
b) Losing prop blades.
c) Falling off the wing into the ocean.

But if you flew the Strat.... we're envious :)

4th May 2007, 20:24
Three retired F-27 pilots were discussing world affairs one very windy morning.

"Windy, isn't it?" opined the first.

"No, it's Thursday" said the second.

"Yeah, me too'' said the third, "let's go for a beer." ;)

4th May 2007, 22:58
Pigboat, I'd aver you were in the pub with me tonight, except you appear to be several thousand miles further west...

PT, I agree; 411A, they had to be Basler DC-3s. But I 'm with you on the radials... my favourite sound is that of four R2800s thrusting a DC-6 over my head in the wee hours in the UK out of Heathrow until fairly recently. That and the Tigercat, we are going to miss that particular delight in the UK.

5th May 2007, 01:41
WHBM mentions Stratocruisers sheding propellor blades.
Yes, this is true, BUT this only occured with those fitted with CurtisElectric props.
On these, the blades were steel, and subject to repetative fatigue fractures.
Most, if not all operators later switched to the Hamilton Standard Hydromatic props, and these sort of problems disappeared.
In addition, the R4360 engine in addition to being equipped with a supercharger (blower) also employeed a General Electric turbocharger, for enhanced high altitude performance.
It was a very fast airplane...300KTAS was not uncommon.
Having said this, is sucked up fuel like a big Hoover...500 gallons/hr.
Nearly as much oil as well....:uhoh:

I posted the following on a private forum, in answer to a question about these Curtis props...

I personally witnessed this terrible accident, and oddly enough, this was the only DC-6 ever produced equipped with Curtis Electric propellers.
When a propeller malfunctions, or as in this case, a blade separation, the results are many times quite fatal.
The 'ole DC-6 was a wonderful airplane to fly, and it does surprisingly well on two engines, but not with the landing gear extended.


Here is another example of a propeller problem.
All DC-6's that I flew were equipped with a Martin Bar, and it surely was necessary.