Subject: Number One Hundred in the Series--North American F-100 Super Sabre (11 of 12)

From: [email-masked]
Date: 10 Nov 93 16:24:14 GMT

>From [email-masked]

In the mid-1950s, NATO officials became concerned with the possibility 
that Soviet nuclear weapons could obliterate Allied aircraft sitting 
on the ground at their airfields in a surprise attack, leaving NATO 
powerless to retaliate.  One of the potential cures for this problem 
was to disperse aircraft in hardened shelters far away from targeted 
airfields, and having these aircraft launched by rocket propulsion 
from special platforms.  The concept was known as Zero-Length Launch, 
or ZEL for short.  

A contract change made on October 12, 1956 stipulated that NAA would 
build the last 148 F-100D aircraft with ZEL capability.  Two F-100Ds 
(56-2904 and 56-2947) were loaned by the USAF to NAA for tests of the 
ZEL system.  

In order to launch the F-100D, NAA's Rocketdyne division developed a 
solid-fuel rocket motor that would be attached to the bottom of the 
rear fuselage.  This engine was capable of delivering a thrust of 
130,000 pounds for four seconds.  This was sufficient to accelerate 
the F-100D from zero to 300 mph in four seconds.  Following burnout, 
the rocket motor would drop off the aircraft, leaving the Super Sabre 
free to fly.  

The first five launches took place with dummy airplane-shaped masses 
attached to the rocket motor.  The first such launch took place on 
December 12, 1957.  

The first live launch of an F-100D took place on March 26, 1958.  On 
that day, test pilot Al Blackburn climbed into 56-2904, started the 
engine, pushed the throttle to full afterburner, then lit the rocket 
motor.  Within four seconds, he was flying at 300 mph.  The rocket 
booster dropped off, and Blackburn entered the standard pattern and 
landed safely.  

On his second flight, things did not go so well.  After burnout, the 
rocket motor would not drop off the aircraft and Blackburn was forced 
to eject.  However, the remaining of the total of 20 launches were 
incident-free.  Airplanes taking place in test launches carried 
standard underwing stores, including dummy nuclear weapons.  

Although the system was reliable and relatively simple to operate, it 
was never deployed operationally.  

Sources:

  North American F-100 Super Sabre, David A. Anderton, Osprey, 1987

  The North American F-100 Super Sabre, Ray Wagner, Aircraft in Profile,
  1965.

  United States Military Aircraft Since 1909, Gordon Swanborough and
  Peter M. Bowers, Smithsonian, 1989.

  The American Fighter, Enzo Angelucci and Peter Bowers, Orion, 1987.

  Fighters of the United States Air Force, Robert F. Dorr and
  David Donald, Temple Press Aerospace, 1990.

Joe Baugher		AT&T Bell Laboratories   	
2000 North Naperville Road      Naperville, Illinois 60566-7033