Ordnance Corps |
THE MALPAIS MISSILES by J. P. Moore Comments and Extract from J. P. Moore's book |
Air Defense Artillery |
Hi Doyle,
I'm J. P. Moore, a retired USAF Msgt who did 3 years in Army before switching. You may use this e-mail on your great web site if you wish. I hope it is not too lengthy. You may edit anything for length and content EXCEPT the story quoted from my book.
I now live in Shreveport, LA and have friends in Silver City, NM w/zia.net address. You near there?
As an IFC type on Nike Ajax in 1954-1957, I spent my entire three year tour at
White Sands Proving Ground, between Red Canyon Range Camp and an Ajax site
down near the main camp at WSPG, CONARC's Board Number 4 site. Our Nike Ajax
set was serial number 02. Few Nike folks know that before there was a
modification to equipment at a tactical site , we tested that mod at Board No.
4. One that comes to mind was the dual trace, "sum over error" presentation
on the tracking "A" scopes. The first Ajax tracking scopes had a single gated
line and the field tests for the dual trace were done while I was at Bd. No.
4. I didn't like dual trace, but it was sent to the field despite my
objections. :-) There were six of us at Bd. No. 4 IFC, CWO Dickerson (Mister
D), two Master Sgts, and three of us PFCs. In the one year I was there, we
launched between 80-100 missiles. I have written a book about my wonderful
Nike Ajax days called The Malpais Missiles and what follows is the story of
one launch from Bd. No. 4. BTW, The Malpais Missiles is available at the WSMR
Museum Gift Shop, The Gift Gallery in Carrizozo, NM, and by writing to me at
malpaismsl-2@sport.rr.com.
Parallax means parallel axis. It is the angle formed by two different views of an object. Try it yourself: with both eyes open, point at a small object across the room. Most people have a predominant right eye, so close your left eye now. Are you still pointing at the same spot? Open your left eye and close your right eye. You’re not pointing at it now, are you? That is a parallax error, and it’s caused by the small distance between your eyes. A Cyclops wouldn’t have this problem.
The two tracking radars, like your eyes, present two different views. Because of their great physical distance apart, they create a huge parallax error. The computer must have accurate data which appears to come from one central point, like a Cyclops. Why can’t we do this by putting a parallax correction in the computer? What if we subtract the physical distance between the two radars and fool the computer into believing they are as one, both occupying the same virtual space?
The exact position of our tracking radars has been meticulously surveyed and they are aligned to within a few arc seconds of True North. The physical distance between the two radars is carefully measured in three axes: north-south, east-west, and the difference in elevation, in case one of them is on a hill or in a valley. All measurements are made from the center of the Target Track Radar, which is ground zero. These data are then fed into the computer by setting three control knobs, effectively subtracting the distances. The computer is fooled, and it now thinks both radars occupy the same virtual point on the earth’s surface. Therefore, their axes are always parallel. “That’s great to know," you say, “but so what?” Read on.
Early in the Nike testing program it was recognized that the RCATS could not come close to simulating the actual aircraft that the system was designed to stop. The RCAT with its corner reflectors does present a good radar target. However, let’s face it, they are agonizingly slow and can’t begin to reach the higher altitudes at which real bombers typically cruise, say 35,000 to 40,000 feet MSL (above Mean Sea Level). In short, the RCAT doesn’t present a realistic challenge for the Nike system. What is needed is a real, jet powered, high performance target.
“Okay," says the Air Force, “we’ll equip a jet fighter aircraft with remote controls, at a cost of many thousands of dollars. And we will fly it around while you guys shoot at it, but you had better not hit it.” “Not to worry,” the Army replies, “we will simply program a parallax error into our computer, and the missile will miss the target by that distance. Your fine airplane will not be shot down, and we can achieve the realistic testing we need. Everyone will be happy.” The uneasy (at best) working relations between the two branches is about to get much, much worse. The Army doesn’t like having to deal with the Air Force, and the Air Force sure as hell doesn’t trust the Army to intentionally miss a chance to shoot down an Air Force jet fighter.
Reluctantly, a jet fighter plane (probably an F-80) is rigged with remote controls to act as a target for us. This is very tricky business. If the Nike should accidentally hit the aircraft and cripple but not destroy it, the plane could stray off course and fly for miles, causing all sorts of nightmares. Remember Roswell?
In addition to the remote controlled plane, a chase plane with a real pilot is needed. A plane that can stay at a safe distance, many, many miles away, yet capable of overtaking and downing the wayward target plane before it leaves the range, if necessary. Additionally, I believe another plane is used from which a pilot flies the remote drone, after a ground controlled take-off. This is beginning to get expensive. No wonder we use RCATS.
Finally all is ready. We have had our equipment powered up for more than 24 hours to get it warmed up and stabilized. The agreed upon miss-distance is put into the computer by way of a parallax error. Here is where the already precarious mutual trust factor goes down the tube. The Air Force insists upon and receives permission to station one of its officers in both the Fire Control Van and the Radar Van as observers, evidently guarding against any hocus-pocus. Additionally, an Air Force officer is in the Launch Control Van, down near the missiles.
The settings for the parallax error are checked and double checked by all concerned and pronounced okay. I think there was even some kind of a seal put on the three parallax dial knobs (North/South, East/West, and Elevation Difference Up/Down).
The parking lot out in the sand dunes is
chock-full of staff cars. This is turning out to
be the event of the season, and everybody wants
in on the action. The normally hot vans are
almost unbearable from the extra body heat.
Launched from Holloman AFB, the remote controlled fighter jet and its escort(s) quickly climb to their assigned altitude. There the drone begins its long, oval flight plan, while the chase plane remains a safe distance away. We are tracking the drone all the while, making sure everything is ready. I’m at the Range control of the target tracking radar. On my left is the other PFC Moore at Azimuth and PFC Crispin at Elevation. We sit almost shoulder to shoulder. The tension is palpable. Nobody says a word except for running the pre-launch checklist. I can literally feel the eyes of the Air Force officer burning the back of my neck. I’m praying that nobody screws up now.
Master Sergeant “Pappy”, the Missile Tracking Radar operator, has the selected missile locked in the gate of his scope. The missile’s on-board transponder acknowledges receipt of commands from the radar. We are ready. The drone comes out of the turn at the northern end of its oval course and begins the straight leg toward us. Over in the Fire Control van, Mr. D raises the red safety cover over the firing control and pushes the switch. “Missile away!” reports Pappy, his range and elevation dials spinning madly as the booster blasts the Nike toward the stratosphere. It will all be over in less than one minute.
I glance out of the corner of my eye at the Target Azimuth and Elevation scopes and everything looks good. The target is locked solidly in the gate of all three of our scopes. The TTI indicator shows less than one minute to go. It seems like an eternity. I hold my breath. The TTI shows 30 seconds, 5, 4, 3, 2, 1 seconds, then 0. I can hear the missile track radar servos as they automatically return the antenna to the stowed, vertical position, its mission completed.
Because we have intentionally missed the target, there is no bloom on the Target Track scopes from the warheads burst. We continue to track the target. Now I notice that my range rate indicator is changing, gradually slowing. I look at Target Azimuth and it’s holding steady. Then I see the Target Elevation dial, and it’s beginning to unwind, slowly at first, then faster. The target aircraft is falling. The unthinkable has happened.
We have shot down the Air Force’s aircraft despite the programmed miss-distance. We rush out of the van, almost running over the Air Force observer, who doesn’t yet realize what has happened. Once outside, far to the north we can see a long black trail of smoke as the stricken jet falls from the sky. We are at once thrilled and very scared
If I thought we were going to call it a day and go home, I had another thought coming. More staff cars are roaring into the sandy parking lot, with brass pouring out and heading for Mr. D. Those wearing Army uniforms return his salute and shake his hand, smiles a foot wide. The others are not quite as cordial, and demand to see the parallax dials for themselves, looking for a clue.
While 25 people are trying to get into a Nike van built for six, a civilian car drives up, and two men in civilian clothes get out. They open the trunk, and produce, not a machine gun as I expected, but an iced pony-keg of beer. They tap the keg, set out paper cups, and leave. No one knows who they are. Although offered a cold glass of beer (everyone is sweating profusely, and not just from the heat), the Air Force brass declines, and eventually they speed away in their staff cars.
Shortly after the Air Force brass leaves, Mr.
D gets a phone call on the PBX switchboard
from the Commander of WSPG, Army Major
General William Bell, congratulating Mr. D and
the entire Board Number 4 crew, and he closes
with “Enjoy the beer.”
Of course, the event recorder chart and the plotting board charts are confiscated for analysis, as well as the film from the tracking radar cameras. I don’t think it was ever learned exactly what brought down the jet drone.
The Nike Ajax warheads, there are three of them, are made of a high explosive called Composition B, which is layered with small hardened metal cubes, the shrapnel. Total weight: 300 pounds, about 25% of the weight of the missile. All it would take is for one cube, not much more than a quarter of an inch square, to pierce a hydraulic line or to zap a critical electronic control component and the aircraft could be fatally wounded.
All indications were our missile flew and detonated exactly as programmed. I think someone simply underestimated the kill radius of a Nike’s warheads. We never shot at another actual aircraft while I was assigned to Board Number 4, only the little red RCATS.