Your final statement is broadly correct, and probably includes the accident type.

But your first two paragraphs regarding the DC-3/C-47 are sweeping statements, Eric. Goes without saying the performance varies enormously with the conditions, as well as the all-up weight. In a sea-level, UK-based public-transport operation in the late 1960s, we had to demonstrate - following an engine-failure soon after take-off - a climb to circuit height, followed by a circuit, approach and landing. The CofA-renewal air test recorded the rate-of-climb figures on each engine separately. Admittedly these were done at fairly low weights, but the expectation was that the aeroplane was flyable on one engine up to our MTOW of 28,000 lb in temperate conditions. Not that we would have wanted to put that to the test, because we preferred to nurture our old Twin Wasps...

In the same airline group at the same time, to put the above in context, the twin-jet BAC One-Elevens were operating under Performance "A" rules which - as fox niner states above - demanded a single-engine, second-segment climb-gradient of at least 2.4%.

Chris

Of course Performance will vary enormously with weight and density altitude. I'm not disputing that.

I'm not disputing that the DC-3 will fly on one engine - it was designed to. At lower weights it may even climb on one engine - however to the best of my knowledge this wasn't part of the original certification. That is why I used the word 'maintain' - which I believe was also used in the Douglas advertising for the type.

I have had an engine failure in the DC-3. It was cold and the density altitude was very low. With climb power on the good engine I was able to maintain altitude with a speed of 95 knots. The aircraft was well below maximum weight.

The important point is that operating these older aircraft needs to be done with the realisation that they may be certified to different standards. They may not have the Performance margins that more modern aircraft have.

Yes, I also experienced an engine failure on a C-47 Dakota with 3 tonnes of newspapers and mail on board, but it happened at F/L 70. Hence no need to climb during the diversion. Had the ILS approach through low stratus led to a go-around, however, we fully expected it to be successful.

Eric, you do not need to convince me that the certification requirements for single-engine performance on twins have risen enormously since the DC-3 was certificated in the 1930s, and again since the Convair 340 in the early 1950s. I fully agree that those inexperienced on such older types need to be made aware of that. But there is no need to exaggerate to make the point. You wrote that, in the DC-3/C-47, "Trying to climb engine-out will quickly put you below Vmc unless you are empty."

One interesting observation of better modern single engine climb performance is with control zone steps. I used to think of them as step downs but was told that the steps were set by single engine climb performance. For example the steps south of Gatwick have been significantly changed in the last 20 years or so to give higher uncontrolled air space/higher steps as single engine performance is so much better.

That is a salutary lesson that many should review! :eek:

OAP

No. Its part of the discussion.

Yes, it may seem like that at times... The problem is that a rare example of a significant, post-war aircraft has been lost and it appears that no one with experience on type is available and willing to contribute. So old farts like myself with some familiarity of other big-radial airplanes are about as good as you're going to get in advance of the accident report.

Of course there are those on PPRuNe who take exception to any speculative discussion of an accident - see at least one post regarding the JU-52 accident yesterday. My opinion is that we can all learn from (and perhaps even contribute to) the sum of human knowledge in the aerospace field if we are prepared to read and/or contribute with any degree of authority and honesty to such conversations. A significant, if small proportion of our speculative discussions on the possible fate of AF447 were a case in point. Once an accident report has been published, the incentive to contribute ideas is reduced.

In advance of a definitive report almost all discussion is speculative. Cut that out and you are left with photos of wreckage and mawkish expressions of sympathy to the bereaved.

+1, Sir.

Keep on posting, please.

Thank you Chris. A timely reminder of the benefits of having people of your experience and knowledge being allowed to speak (i.e. post). It is not going too far to evoke the old cliche - "pearls of wisdom". (I thought the MH370 threads were being hampered by the weight of trite comment. In this case the final report begs more questions than it answers. )

There are more things in heaven and earth, Horatio,
Than are dreamt of in your philosophy.
- Hamlet (1.5.167-8), Hamlet to Horatio

Fuel type
 

Well spotted.

I questioned the refuelled type of fuel quite in the beginning of the thread but my posting was deleted :(
Large airplanes have the risk the refueller automatically takes the Jet A truck... as are planes with "turbo" on the nacelles close to the fuel cap.
Anyway if it will show it was the reason for the crash it will be sickening for all those who got hurt.

So who exactly is questioning the fuel type?

I find this bit of speculation a tad unlikely, a piston engine fed with a mixture of avgas and kerosene would trail a cloud of white smoke from both engines and a distinctive smell of partially burned kero.
This does, of course, depend on the amount of good avgas in the pipeline and on the mixture percentage in the tanks.

Are you sure you don't mean the DC-4 at Francistown? Not a DC-6.

Using Jet fuel doesn't explain the fire.

Happened to a DC-6 in Fairbanks. Alaska. I know a guy who was a witness to the accident.

In the above referenced accident, the guy who was there told me that as the plane took off, there were long yellow flames coming from the exhaust stacks as the plane took off. He was a mechanic for the airline, so was familiar with what a normal exhaust flame looked like on a DC-6 taking off. That said, the flames in the video appeared to be coming from under the nacelle, not out of the augmenter, which is where I'd expect an exhaust flame to be. On the other hand, running a gasoline engine on jet fuel often results in catastrophic detonation. If it blew the head off a cylinder (which is within the realm of possibility) there would be plenty of engine oil running around loose, heat and sources of ignition. I wouldn't say that the fire in the video is ruling out mis-fuelling.