Machining Blog

A few nice precision grinding solutions photos I located:

Apollo 14 Docking Ring

Image by jurvetson
Milled from a strong block of titanium, with twelve docking latches, it’s a marvel of precision design in the era just before CAD/CAM.

The Smithsonian believed this was the CM docking ring from Apollo 14 Command Module, and had paperwork to assistance that. I believe it is the sister unit, a massive structural engineering element employed for ground testing to try to recreate the series of docking failures experienced early in the Apollo 14 mission with the probe that was brought back (normally the docking probe would be left behind). Hence the Apollo 14 label on the base and description at the Bonhams’ auction:

NASA’s selection to fly Apollo missions using a lunar orbit rendezvous method required the development of a system to join, separate, then rejoin two spacecraft. This method also had to enable astronauts to move internally amongst the Command and Lunar Modules. The flight configuration chosen was an impact technique consisting of a probe situated at the forward end of the Command Module (CM) and a funnel-sort drogue positioned at the best of the Lunar Module (LM). The CM’s probe was mounted to the docking ring, which supplied a point of structural integrity for the two docked cars once the probe was removed. Removal of the probe developed a tunnel so the crew could travel among the docked automobiles. A series of latches about the docking ring locked the vehicles with each other. The tip of the probe had a set of 3 small capture latches which were created to hold the cars collectively extended enough that the bigger docking ring latches could be engaged.

Just following the Saturn V’s third stage sent Apollo 14 on its planned trajectory toward the moon, Shepard along with astronauts Edgar Mitchell and Stuart Roosa skilled difficulty docking the CSM to the LM. Five attempts have been made but the docking probe capture latches never ever engaged to safe the two cars with each other. This could have scrubbed for the second time in a row a lunar landing mission. With the failure of Apollo 13 due to a Service Module oxygen tank explosion, a scrub of the Apollo 14 lunar landing would most surely have provided ammunition to those in Congress lobbying for an early termination of the Apollo System.

Right after nearly 2 hours of delays and on the sixth attempt, with Roosa holding the CSM tight with the LM for several seconds, the latches ultimately engaged. The crew then activated the series of larger latches mounted along the docking ring to obtain a &quothard dock&quot configuration. Though they were lastly docked, Mission Handle and the crew’s concern shifted to the possibility that the method could fail when it was most required, the redocking of the LM Ascent Stage following Shepard and Mitchell’s return from the moon. If this occurred the crew could be forced into performing a space walk in order to return to the CSM. The lunar rocks and scientific data may possibly have to be abandoned in the LM pending the precise situations of a potential lunar orbit docking issue. The probe was thoroughly inspected by the crew for the duration of the coast period to the moon and they sent detailed verbal descriptions plus tv photographs to Mission Handle. Considering that the probe now showed standard operation of the capture mechanism, NASA created the selection to proceed with the planned mission.

The redocking while in lunar orbit was completely regular. The docking probe (usually jettisoned with the LM) was returned to earth for inspection and evaluation.

NASA and spacecraft manufacturer North American Rockwell performed an exhaustive series of tests to the docking program. All components (probe, latches, docking ring) had been tested &quotin place&quot with the recovered Apollo 14 CM, then each was removed for a series of combined and person tests. The docking system dilemma was a major purpose the docking ring was removed and in no way re-installed into the Apollo 14 CM. Post-flight evaluation of tv, motion picture film, accelerometer data, and reaction control system thruster activity indicated that probe-to-drogue get in touch with conditions have been as anticipated for all docking attempts. The probe’s capture latches should have worked on each and every of the first 5 docking attempts. A plunger-kind component in the capture latch failed to attain a forward or locked position most likely due to some type of foreign debris or contamination. A alter in the size of the plunger due to temperature was an further possibility. Internal damage to the capture-latch mechanism was ruled out as the cause because the technique functioned properly in all subsequent operations following the sixth docking attempt and throughout post flight testing. The debris or contamination most likely became dislodged soon after the fifth docking try, enabling the system to operate appropriately from that point. NASA and Rockwell created the decision to give a protective cover on the tip of the probe to prevent contamination in the course of future flights.

Throughout the tests, the ring was shipped in between different NASA and contractor facilities by means of a 39 by 39 by 12 inch wood transit case which is included with the ring. The ring itself has a series of inspection stamps and ID numbers that read: &quotMDR 408699, V36-316250-9, 06361-B009522, MR 361588, DEC 9 1968, V36 316250 31, ASSEM, FEB 18 1969, 06361A015194.&quot A separate 6 by three inch yellow &quotTemporary Components Removal Tag&quot repeats several of these numbers and has the extra hand-written details of: &quotTPS 112, REM #103, Docking Ring, S/C 110, two/14/72.&quot

Included are copies of documents listing the NASA artifact quantity (2243) becoming from Command Module (S/C # 110) for the transfer to the National Air and Space Museum (NASM) and deascession papers from NASM.

The Apollo 14 docking ring is the single largest and heaviest piece of lunar spacecraft structural gear ever to be provided to private hands. The flown CM docking ring, the twin of this 1, remained with the ascent stage of the Lunar Module Antares when it was jettisoned. Antares was then deliberately crashed into the moon’s surface to simulate a &quotmoonquake.&quot

Santa’s 12th Nutcracker Regiment marching to Molotov’s from the Castro

Image by Steve Rhodes