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July 20, 2021 Archives

Tuesday, July 20, 2021

CONTINUITY: Did the USS Thresher Crew Survive the Initial Mishap?

On April 10, 1963, the nuclear powered attack submarine USS Thresher (SSN-593) was lost during sea trials in the Atlantic Ocean east of Cape Cod in Massachusetts, with no survivors among the 129 crew and shipyard employees on board. An inquiry concluded that a failure had resulted in an uncontrolled dive which caused the hull to implode at a depth between 400 and 610 metres, instantly killing all aboard. Much of the investigation and supporting documents was classified secret and remained so for decades.

In response to a Freedom of Information Act lawsuit filed by a former Thresher-class submarine commander, the Navy has been releasing documents from the investigation in a series of batches, with the most recent on July 9, 2021. All of the releases to date are available here.

Here is an analysis of the most recent 600 page release, including reports from the USS Seawolf, which conducted search operations starting the day after contact was lost with Thresher. Seawolf detected what were interpreted as pings and metal banging noises from Thresher, but the court of inquiry concluded, “That while operating as a unit of the search force, the U.S.S. Seawolf (SSN575) recorded possible electronic emissions and underwater noises. None of the signals which SEAWOLF received equated with anything that could have been originated by human beings.”

The following analysis argues that it is extremely difficult to explain the contemporary reports from the Seawolf on multiple dives near Thresher's last reported location as having any possible origin other than crew surviving on the stricken submarine for at least a day after the accident.

Posted at 15:46 Permalink

CONTEXT: What Good Is Space Tourism? Democrat: “We will tax it!”

This is complete, of course, with a cute acronym, “Securing Protection Against Carbon Emissions”, of which, this idiot is doubtless completely unaware, Blue Origin's rocket has zero.

Posted at 15:19 Permalink

CONTINUITY: A Ride on the Claughton Aerial Ropeway

An earlier post on 2021-07-13, “Powered by Gravity—Britain's Last Aerial Ropeway”, described the last operating cargo ropeway in Britain. At the time, video maker Tom Scott, sent a GoPro Hero 9 camera down the ropeway with a bucket of cargo. The weather could have been better (as is often the case in the British Isles), but this 19 minute video gives the full experience of riding the ropeway with cargo. Note that buckets bound uphill are empty: it's the difference between the up-mass and down-mass that powers the ropeway.

Posted at 11:36 Permalink

THE HAPPENING WORLD: SpaceX: Starship Super Heavy BN3 Successful Static Fire Test

As Elon Musk noted, this test involved only three engines on the booster, as I understand, one in the centre ring and two in the middle ring. There's no reason to risk the full complement of engines until the ground support systems, fuel delivery, plumbing, and firing and safing systems have been validated.

Posted at 11:26 Permalink