Subject: Number One Hundred in the Series--North American F-100 Super Sabre (5 of 12)

From: [email-masked]
Date: 28 Oct 93 14:19:26 GMT

>From [email-masked]

The F-100C fighter-bomber was the first fully combat-capable version 
of the Super Sabre, and was the first version of the Super Sabre to 
serve with the USAF in really large numbers.  

In October 1952, even before the YF-100A had taken off on its first 
flight, the USAF asked NAA to look into the possibility of developing 
wings for the Super Sabre that could carry fuel.  In July of 1953, the 
USAF asked that the new "wet" wing could be made sufficiently strong 
enough to carry additional external ordinance.  This concept 
eventually emerged as the F-100C fighter-bomber version of the Super 
Sabre.  

On December 30, 1953, the USAF revised the original F-100A production 
order and stipulated that the last 70 planes on that order be 
completed as fighter-bombers under the designation F-100C (company 
designation NA-214).  On February 24, 1954, the Air Force ordered an 
additional 230 F-100Cs.  

In order to provide a prototype for the F-100C project, the fourth 
production F-100A (serial number 52-5759) was taken out of the test 
program and modified.  However, because of the difficulty in 
incorporating integral fuel tanks in an already-constructed airframe, 
52-5759 remained a dry-wing aircraft.  It flew for the first time on 
July 26, 1954.  This aircraft was delivered with the short vertical 
tail of initial F-100A aircraft, with the taller vertical tail being 
fitted later.  

The F-100C introduced wing modifications that added hard points on the 
lower surface that could be fitted with removeable pylons that could 
hold either fuel tanks or weapons.  These six underwing stations could 
accommodate a wide variety of stores including fuel tanks, napalm, 
bombs, up to a dozen five-inch HVARs (high-velocity air rockets), and 
even "special stores" such as the MK-7 nuclear weapon.  A total of 
5000 pounds could be carried on these stations.  The wing was locally 
strengthened to withstand the sudden shock of weapons release.  

In order to accommodate the fuel in the "wet" wing, the wing's 
integral systems had to be redistributed.  A leak proofing system was 
devised in which all bolts that fastened skin to spars were sealed 
with injected material.  In the final design, the F-100C "wet" wing 
could carry 451 US gallons of fuel.  Total internal fuel capacity was 
1602 gallons, as compared with 744 gallons for the F-100A.  

The F-100C had provision for single-point ground refuelling, a major 
improvement over the gravity-filling of the fuselage tanks in the 
F-100A.  A wing-mounted detachable refuelling probe was added which 
made the F-100C capable of in-flight refuelling.  

The first production F-100C (53-1709) rolled off the line on October 
19, 1954.  It was conditionally accepted by the USAF on October 29, 
since all Super Sabres were officially grounded at that time pending 
the fitting of new vertical tails.  It took to the air for the first 
time on January 17, 1955, with NAA test pilot George Hoskins at the 
controls.  It had the original short F-100A tail, but was later fitted 
with the new taller tail.  

On May 27, 1954, an additional USAF contract increased the total 
number of F-100Cs to 564, more than doubling the initial order.  
However, on September 27 the contract was amended to stipulate that 
the last 224 aircraft on the order be completed as F-100Ds.  

On October 11, 1954, North American's Columbus, Ohio plant was 
designated as a second source for Super Sabre production.  
Columbus-built F-100Cs were designated NA-222 by the company.  Air 
Force designations distinguished Columbus-built machines from 
California-built machines by using the suffix *NH* rather than *NA*.  
A contract was let which authorized the construction of 25 F-100Cs at 
Columbus, followed by 221 F-100Ds.  The first of 25 Columbus-built 
F-100Cs (55-2709) took off on its maiden flight on September 8, 1955.  

Provision had been made for an additional pair of 200-gallon drop 
tanks to supplement the pair of 275-gallon drop tanks usually carried.  
However, the addition of these smaller tanks caused some longitudinal 
stability problems, especially at high cruising speeds.  For a while, 
it seemed that the only cure for this problem would be yet another 
time-consuming and costly increase in the surface area of the vertical 
tail.  Paradoxically, the use of larger fuel tanks cured the problem, 
and both the 275- and the 200-gallon tanks were replaced by a single 
pair of 450-gallon tanks.  However, these bigger tanks were costly and 
were rarely carried.  A change to 335-gallon tanks was later made.  

F-100C deliveries to TAC began in April of 1955.  The first outfit to 
receive the F-100C, the 450th Fighter Day Squadron at Foster AFB in 
Texas, became fully operational on July 14, 1955.  By the end of 1956, 
F-100Cs were serving with the 8th Fighter-Bomber Group in the Fifth 
Air Force in Japan.  

The first few F-100Cs were powered by the J57-P-7, rated at 9700 
lb.st. dry and 14,800 lb.st. with afterburner.  This engine was soon 
replaced on the production line by the J57-P-39 with similar rating.  
However, most F-100Cs (from the 101st machine and onward) were powered 
by the J57-P-21, an upgraded version of the J57-P-7.  The -21 was 
rated at 10,200 lb.st. dry and 16,000 lb.st. with afterburner.  This 
engine provided more thrust at higher altitudes, and increased the 
speed at altitude by about 40 mph and reduced the time to climb to 
35,000 feet by about ten percent.  

One of the more serious defects of the F-100C was that this aircraft, 
like the F-100A before it, tended to yaw and go into an uncontrollable 
roll at high speeds.  Beginning with the 146th production F-100C, 
hydraulically-activated and electrically-controlled yaw dampers were 
incorporated on the production line.  This innovation seemed to help 
to alleviate this problem, and was retrofitted to earlier F-100Cs.  

Beginning with the 301st F-100C, pitch dampers were added to the 
horizontal stabilizer control system.  This helped to damp out 
longitudinal oscillations, which had been an ongoing problem with the 
Super Sabre.  

The J57 engine of the F-100 suffered from a problem with compressor 
stalls.  A partial cure for this problem was the installation of a 
pressure bleed-off which helped to release the accumulated gases and 
to prevent internal explosions.  

On August 20, 1955, Col. Horace A. Hanes flew a F-100C to set a new 
world's air speed record.  In two runs made at an altitude of 40,000 
feet in opposite directions over a 15-25 km course laid out on the 
Mojave Desert, he averaged 822.135 mph.  This was the first supersonic 
world's speed record.  It was also the first record set at high 
altitude, all previous record-setting runs having been made at very 
low altitudes.  

On September 4, 1955, Col. Carlos Talbott flew his F-100C across the 
USA from coast to coast, a distance of 2325 miles at an average speed 
of 610.726 mph.  For this feat, Col. Talbott was awarded the Bendix 
Trophy.  

A total of 476 F-100Cs were built, the last example being accepted in 
July of 1956.  

More than 150 F-100Cs served in Europe.  Major bases were at Bitburg, 
Furstenfeldbruck, Landstuhl, and Hahn in West Germany, plus Sidi 
Slimane in Morocco and Camp New Amsterdam in the Netherlands.  

The service of the F-100C with the USAF was relatively brief, being 
rapidly superseded by the F-100D.  Ex-USAF F-100Cs were passed along 
to the Air National Guard (ANG), the first squadrons receiving the 
type in mid-1959.  Most of the F-100Cs remaining in the Air Force 
active inventory in the late 1950s served exclusively in training 
roles.  

On October 1, 1961, President Kennedy mobilized the ANG in response to 
the Berlin Crisis.  Many of these mobilized ANG squadrons were 
transferred to Europe to augment NATO, but three ANG squadrons 
equipped with newly-received F-100Cs stayed in the United States.  
This included the 120th TFS, the 121st TFS of the Washington DC ANG 
and the 136th TFS.  All of these ANG squadrons were demobilized in 
August of 1962.  

By mid-1966, 210 F-100Cs were in service with the ANG.  However, on 
January 25, 1968, in response to the *Pueblo* incident, President 
Johnson mobilized a major portion of the Selected Reserve Force, which 
included eight ANG squadrons equipped with F-100Cs.  The last of these 
F-100Cs were phased out in March of 1970, and by late 1970 ANG F-100C 
strength was back up to 210 aircraft.  

The only F-100Cs to fly in combat in Vietnam flew with ANG units which 
had been called up for that conflict.  A total of four ANG squadrons 
(from Colorado, New York, Iowa, and New Mexico) flew F-100Cs in 
Vietnam.  

The USAF Thunderbirds flight demonstration team operated F-100Cs from 
1956 until 1964.  Thunderbird F-100Cs were painted in picturesque red, 
white, and blue colors, with the characteristic Thunderbird being 
painted on the aircraft's belly.  They were replaced by F-100Ds in 
1964.  

A total of 476 F-100Cs were built.  The safety record of the F-100C 
was not all that good, some 85 of them being involved in major 
accidents.  

As they left operational service, a few F-100Cs ended up serving in 
test roles.  NACA (and later NASA) operated a pair of F-100Cs (53-1712 
and -1717) plus one JF-100C (52-1709).  The first F-100C was used to 
test a pitching motion damper.  The second F-100C was used to fly 
chase support.  The JF-100C was used for variable stability studies 
supporting the X-15 and supersonic transport programs.  F-100C 54-1964 
was loaned to the Ames Research center for tests of a boundary layer 
control system.  It had a thicker inlet lip, a drooped leading edge, 
and ducting to carry bleed air from the engine compressor to the wing 
leading edge.  

F-100C-1-NA 54-1753 is on display at the USAF Museum at 
Wright-Patterson AFB in Ohio.  

53-1709/1778 	North American F-100C-1-NA Super Sabre (NA-214) 
54-1740/1769 	North American F-100C-1-NA Super Sabre (NA-217) 
54-1770/1814 	North American F-100C-5-NA Super Sabre (NA-217) 
54-1815/1859 	North American F-100C-15-NA Super Sabre (NA-217) 
54-1860/1970 	North American F-100C-20-NA Super Sabre (NA-217) 
54-1971/2120 	North American F-100C-25-NA Super Sabre (NA-217) 
55-2709/2733 	North American F-100C-10-NH Super Sabre (NA-222) 

Specifications of the F-100C: 

One Pratt & Whitney J57-P-21 turbojet, 10,200 lb.st. dry and 16,000 
lb.st. with afterburning.  Wingspan 38 feet 9 inches, length 47 feet 
1 1/4 inches, height 15 feet 6 inches, wing area 385 square feet.  
Maximum speed 760 mph at sea level, 924 mph at 35,000 feet.  Initial 
climb rate 21,600 feet/minute, climb to 35,000 feet in 2.3 minutes.  
Service ceiling 38,700 feet, combat ceiling 49,100 feet.  Normal range 
572 miles, maximum range 1954 miles.  Fuel capacity 1702 US gallons 
internal, total of 2139 US gallons with external tanks added.  Weights 
were 19,270 pounds empty, 27,587 pounds gross, 32,615 pounds maximum 
takeoff.  Armament consisted of four 20-mm Pontaic M-39 cannon, plus
external loads of up to 5000 pounds of bombs, rockets, or fuel tanks
carried on six underwing hardpounts.

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.

  American Combat Planes, Third Enlarged Edition, Ray Wagner, Doubleday,
  1982.

  Post-World War II Fighters, 1945-1973, Marcelle Size Knaack,
  Office of Air Force History, 1986. 

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