Better inform the FAA quick, they have it as an C-131F ;)

Is that even possible? I'm not a Convair expert but I seem to recall that a 340 had a longer wing than the 240.

The plane in the photo is obviously a piston Convair, but looking in the FAA aircraft registration database doesn't necessarily tell you whether a plane is a 580, a 580 will still be registered as a CV340, or CV440. For aircraft certification purposes, a 580 isn't an aircraft type, it's an STC modification.

The 240 was certified under CAR 4b, effective 1946. that version of the CAR contained a requirement for OEI performance CAR 4b.116.

Link posted on the internet of a remarkable video from a light aircraft showing the last minutes of this flight. Image quality is limited, but confirms that it was struggling to hold altitude before crashing:

From what someone has posted here, the density altitude would have been about 5,700 ft. That would not be good for performance on a limited performance aeroplane. That was a long way that they struggled with it.

Very sad indeed. FYI United States FAA SFP ( Ferry Permit ) for aircraft that size not on FAA121 AOC/Ops specs. Essential crew only ( 3 max ) plus mechanic all must hold FAA license, this old machine seems was a straight out ferry candidate only. Read she was carrying 19 pax and gear maybe 2000kg I guess to much at her age at 5700 foot field elevation. I hope all are recovering quickly, looks like crew did the best with what they were given.

Good catch! I am jet oriented.

Not sure you can tell that from the video, but it certainly had plenty of speed. Passed that C172/182 like it was standing still!

Perhaps that smoking engine was still producing power at that stage?

Yes the crew certainly put up a good fight. The real reason all? got out alive, is they seemed to have hit the ground "under control", therefore not stalled. A lesson for us all. Unfortunatly the TAS/ground speed would have been high, considering the D.A.

With both pilots alive they should be able to give a good account of what happened to the enquiry, they should be out of hospital soon. There may well be other contributing factors such as problems with the gear or flaps.

Did that require a regulatory-defined takeoff flight path to clear all terrain and obstacles to a specified altitude?

CAR4b-116 defines the takeoff path segments and CAR4-b.120 specifies the OEI takeoff performance. Why is it so astonishing to you that an aircraft certificated in the transport category for airline operations post WWII ans operated by airlines has OEI takeoff performance?

True, but a climb rate specified as a ratio of speed equates to a gradient, even though the gradient isn't stated explicitly.

Not astonished at all. Just trying to learn something about the piston era.

OK, it seemed to me like you were resisting the notion, which seemed surprising coming from someone from the era when seeing Convairs, DC-6's and the like flying for the airlines was pretty common.

When I went to work for TWA in early 1964, they were still flying the Connie. I just missed being a F/E on it. 3 years later I just missed it for my initial captain upgrade. So, I was not exposed to piston planning and performance. TWA had retired the Martin before I came aboard, which would be the closet to the Convair twins.

Before I learned to fly I rode on UAL's DC-6s several times. I didn't have a clue about the airspace or airway structure at the time. I do recall riding from Stapleton to Burbank one Spring (1955) afternoon. There were peaks higher than us on both sides somewhere in the Rockies. The cu was building around us. Suddenly, we were solid IMC and the g-load increased until we popped out going eastbound. That was a learning experience.