Mikes Email:
For a PTS guy the number of “exposures” would be more like 150 times a MONTH! When I got to DM in April 1968 we were downloading propellants or working with the PTS gear every day. The reason was a “Project Yard Fence.” That mod began in Little Rock but when 54 civilians were killed due to a fire with the missile fully fueled and war head in place, the AF changed the mod to require missile removal prior to the mod. 3 sites at DM would be under either PTS setup, downloading or up loading or PTS tear down at any given time. The RFHCO’s at that time only had an hour of air so a PTS guy could be in and out of the silo or transferring propellants from the holding trailers to commercial trailers 6 or 7 times each day. Then after the mods, the leaks just kept coming. They used seals made of beutal rubber. Later the seals were made of Teflon which greatly improved the chances of leaks, but they still occurred.
We had a piece of sheet aluminum that was shaped like a Titan. It was 5’ tall and about 8” wide and was divided stage one to two. On the missile we kept track of the propellant operations we had performed over the years with label gun tape, Terry, when I left in 1980 with 9 missile left to deactivate, the sheet metal missile was almost completely covered with tape.
Ever go into a silo with a known Hydrazine leak? A long story.
When I got to DM, my first PTS operation was at 570-8. A hydraulics guy had tried to pry off a platform actuator. Well he did but dropped the actuator and it hit the stage I fuel tank just below level 5 and caused a “minor” leak. DM replaced the bird and I helped load the replacement. The damaged missile was sent to Martin Marietta in Denver, where they put a plug into the tank. Sent back to DM, it sat in the hanger queen for several years, eventually being installed at 571-7. There it sat on alert for many years. Problem was that every so often the plug would leak. You crew guys would do DSV, look up at the plug and see a wet stain down the side of the tank. The MMT’s would go out with a PVD and finding no readings, clean the stain and go home. In a month or two the process would repeat itself. Finally the bird was removed for some other reason and returned to Martin for repairs.
That bird was sent to Little Rock where it was eventually installed at 4-7. Following propellant uploading, the stage II oxidizer tank pressure went low – a common occurrence for a just loaded missile. During the pressurization the PTS crew dropped the 3 ½” socket from level 2 which bounced into the stage I fuel tank at level 7. The PTS crew said they could see fuel pouring into the silo. It was about 1500hrs. At 0300 hours the following day, the stage I oxidizer tank ruptured and the silo was destroyed in a hypergolic explosion. The guy you talked to might be Jeff Kennedy who along with his best friend Livingston were at the portal in RFHCO’s. Had they not been flying backwards 100 feet into the site fence, they would have seen the silo door on it’s trip a quarter mile to the west. Livingston died the next day. I was there two days later on the accident investigation team and had the honor listening to Jeff give testimony of what he did that night. I was very near tears and will never forget that experience.
End of that story. So did I ever go into a silo with a known leak? A thousand times!
One problem with the RFHCO’s was that if you were in vapors, which was common, and stooped down and then raised up, the air valves would allow the propellants to enter the suit. It was a rite of passing for anyone in PTS.
Have a good one and thanks for the job your doing.
Mike
Another PTS troup on the leaking missile seals:
As for the seals, those things were a time bomb waiting to go off. They should have not been used in the first place.I have seen them where they actually were nothing left but a glob of jelly-like black gunk when I had to change them out.That time, we had to make a "funnel of sorts" out of plastic and catch the leak and let it dissipate into the air but the purpose of the funnel was to keep it from falling onto the rest of the bird below it. What a nightmare that was. The leaks were always there, and, I believe, my opinion, the Air Force knew from the git that the PVDs were not calibrated for the right levels. It seemed as though their line of thinking was "oh don't be so picky, just fix it and come back to base. The air in those silos was at times thoroughly saturated with a fine mist of oxydizer, sometimes my skin would tingle from the exposure. At first, as a "green troop", I didn't know what it was and I was told by my trainers "that's the ox in the air." The would just grin when I would say "are we going to fix it?" Needless to say, I too, soon became accustomed to the mist and thought it was all a-okay, never believing that I would be in the shape I am in today because of it.
From Mike:
The original seals were made from buttel rubber molded into an aluminum ring. Fuel had little or no effect on the seal. But oxidizer would eat the buttel (the black goo) especially if the silo humidity was high (Little Rock - humidity) But all bases had problems with the seal. Yes, you know they leaked - sometimes seriously. I can't figure why they would make a poly funnel except that if the humidity was very high, the leak would draw moisture from the air (hydroscopic) and make an acid mixture. DM classified their leaks by location and other equipment exposure. Any leak in a liquid line had the highest priority. Stage 2 manhole leaks also high priority due to warhead exposure.. Vent lines had a lower levels. But the seriousness of the leak also played a factor. In 1978 -1980 Martin began to replace the seals with a 3-piece seal made of Kalrez (teflon). they were white with aluminum backup rings and they seemed to work very well - even in oxidizer.