posted 04-04-2007 04:04 PM               

• Gemini Land Landing System Development Program, Volume I - Full-scale investigations; Mar 1, 1967 - 172 pages

• Gemini Land Landing System Development Program, Volume II - Supporting investigations; Mar 1, 1967 - 488 pages

posted 04-09-2007 08:18 AM               

The interesting thing is that because the descent rate for the parasail was so high, the vehicle required braking rockets and the photographs at the end of the document are poor, but show some of the tests of the braking rockets and these are really interesting. There is a sequence showing a drop test with the rockets firing to slow the descent.

posted 06-18-2007 11:39 AM               

When I interviewed mission planner Rod Rose a few years ago, he mentioned that he had a large stash of documents on the paraglider. I encouraged him to donate the stuff to the Johnson Space Center archives, but he said was considering his options at that time. I don't know what, if anything, he ever did with them.

posted 07-23-2007 11:09 AM               

If a few well-intentioned experiments had worked out a little bit better than they did, Fort Hood might have a place in the history of space exploration to go along with its long-standing military reputation.

Not only that, but the term "El Kabong" might have survived in popular culture as something of a scientific term instead of a character from a 1960s TV cartoon series.

...such a lofty goal required a certain amount of trial and error. A portion of that trial and error took place at Fort Hood, beginning in 1963 when NASA scientists arrived at the base to experiment with bringing a spacecraft and its astronauts back to earth instead of sea, as was the accepted practice.

Scientists used a scaled-down Gemini capsule during the first two years of testing. The dummy capsule weighed about 400 pounds, or 4,600 pounds less than the real things. Tests with the miniature model went well enough to encourage NASA to test a full-scale model.

The theory of bringing the capsule back to earth instead of sea centered on the use of a parasail-landing rocket system, which might sound simple but is anything but.

The parasail, or parachute, was steered by radio command to operate motors on the capsule. The motors controlled flap angles on the parachute used to steer the direction of the drift.

Altitude sensors suspended below the spacecraft were designed to touch the earth before the spacecraft did, which then ignited two 6,000-pound thrust motors that reduced the speed of the falling capsule from 30 feet a second to less than 10. The capsule landed on a tricycle landing gear and everybody aboard the spacecraft was to live happily ever after, or at the very least they were to live.

The capsule, dubbed El Kabong for reasons that are open to speculation, was dropped from an Air Force Reserve C-119 from an altitude of 11,500 feet at Fort Hood on April 21, 1965. The initial test did not have a happy ending; the capsule landed on its side.

...a trip back to the drawing board resulted in an improved turn motor but the second drop, made while Gemini 4 was circling the earth, did not go well either. Damage to the lines that guide the capsule on its way to earth forced Norman to stop the sequence because he could not guide the chute.

The third time was the charm. A successful drop and landing was made on July 31, 1965 when the capsule landed within 40 feet of its target on Fort Hood's Antelope Mound tank range.

"We've got a winner!" an ebullient Norman cried when the capsule landed upright on its tricycle landing gear.

"This is the first successful landing (of a spacecraft) in this country!" he told reporters. "As far as I can tell, everything worked 100 percent."

posted 04-26-2020 12:34 PM               

A single winch was mounted on the nose gear to control the payout of the line closest to the apex of the paraglider. Apparently it was used to reduce the strain that occurred when the inflated paraglider was released from the nose of the spacecraft and the suspension/control lines took the weight of the spacecraft. During gliding flight it limited the maximum angle of attack of the wing to safe angles.

Pitch was controlled by varying the length of forward and aft control lines attached to the keel of the wing and to a winch mounted inside the spacecraft between the astronauts heads. I am unable to find a specific description as to the actual working of this system. Photos of a Test Vehicle show two separate reels mounted in tandem atop the spacecraft facing fore and aft. It appears that as one pitch cable was shortened, the other was lengthened to shift the center of mass forward of backward. This would alter the angle of attack of the wing.

The roll control system worked in a similar manner using it's own winch, presumably located adjacent to the pitch winch. The roll control lines from the wing enter two openings located at the 10 and 2 o'clock positions just forward of the heatshield. I haven't found any diagrams of the control cable routing but it seems reasonable to assume that pulleys are located internally within these openings, and the control lines continue on to the roll winch.

There is no evidence of this, but prior to wing deployment the control lines from the doors to the wing must reside in a covered trough along the perimeter of the spacecraft, just aft of the crew hatches.

How did the control system function that allowed the astronauts to control the wing? Was it simply a constant speed drive, i.e. deflect the stick in the desired direction for an estimated time and observe the result? Or, knowing NASA, was it actually an attitude hold, or rate command system? There are several methods that could have been used.

Any information pertinent to the above would be greatly appreciated.

The post 1965 versions of the Gemini Familiarization Manual contain no reference to the paraglider system. However, a diagram of the paraglider deployment sequence states the June 1, 1962 version of the Gemini Familiarization Manual as a reference. In this time frame the paraglider was the only method expected to be used by Gemini, so it *should* contain some information. I have been unable to find this older version online.

Does anyone have a familiarization manual with paraglider information?

posted 04-26-2020 08:51 PM               

quote:

---

Originally posted by space1:
From what I have seen of system diagrams the pitch and roll winches were enclosed in the top aft portion of the cockpit structure.

---

posted 04-27-2020 07:22 AM               

I wish my paraglider docs offered as much detailed information as the parasail docs do.

posted 04-27-2020 10:34 PM            

Also, the Gemini tow test vehicle that Jack Swigert rode in did not have any means of ejection. Therefore, he did not wear a parachute, is that correct?