Subject: Number 101 in the Series--McDonnell F-101 Voodoo (1 of 10)

From: [email-masked]
Date: 12 Nov 93 17:15:25 GMT

>From [email-masked]

The McDonnell F-101 Voodoo was the first production fighter capable of 
exceeding 1000 mph in level flight.  

During the Korean War, the USAF had found that the Republic F-84 
Thunderjet fighters escorting streams of B-29 bombers attacking 
targets along the Yalu River in North Korea were incapable of 
protecting their charges against attacks by the faster MiG 15.  The 
more capable F-86 Sabre lacked the range and endurance to provide 
effective escort.  In order to meet this critical need for an 
effective long-range escort fighter, the USAF had originally planned 
on using the Republic F-84F Thunderstreak.  However, the Strategic Air 
Command (SAC) also wanted a much longer range escort fighter, one with 
sufficient range to accompany the Convair B-36 intercontinental bomber 
on its missions.  In February 1951, the USAF issued a requirement for 
a fighter to fill this need.  

Lockheed, North American, Northrop, Republic, and McDonnell all 
submitted proposals.  Lockheed submitted both the F-90 and the F-94, 
North American resubmitted the F-93, and Northrop proposed an escort 
version of the F-89 Scorpion all-weather interceptor.  Republic came 
up with three separate submissions, the F-91 Thunderceptor, the F-84F, 
plus another version of the F-84F powered by a turboprop engine.  As 
its entry, McDonnell proposed a larger and more powerful version of 
its XF-88 penetration fighter prototype.  

The McDonnell submission was judged the winner of the competition in 
May of 1951.  In October of 1951, the USAF released fiscal year 1952 
funds previously allocated to the F-84F and F-86F program to get 
McDonnell's proposal into production right away.  

A program similar to that used in the development of the F-100 Super 
Sabre was to be employed, one in which the ordinary prototype stage in 
development would be completely skipped and full production be 
instituted right from the start.  As the initial production aircraft 
rolled off the line, they would be tested and any changes deemed 
necessary would be introduced on later aircraft to come off the line.  
It was hoped that this strategy would get the new fighter into service 
as quickly as possible.  This was a high-risk strategy, one which 
would give the Air Force a new plane in a hurry if everything went as 
planned, but one which would risk the high costs and long delays of a 
lot of in-service modifications should unexpected problems turn up 
during flight testing.  However, considering that the McDonnell 
proposal was basically a scaled-up XF-88 rather than a truly "new" 
design, the risks were considered minimal.  

On November 30, 1951, the new and improved F-88 was assigned the 
designation F-101.  A Letter of Intent for the development of the 
McDonnell proposal was issued on January 3, 1952.  

In December of 1951, the McDonnell team lead by Edward M. Flesh 
recommended that the F-101 be powered by a pair of afterburning 
Allison J71 turbojets.  This nearly tripled the thrust of the pair of 
Westinghouse J34s that had powered the XF-88A, and was twice the 
thrust of the Westinghouse J46s proposed for the production F-88.  
However, the Air Force was in favor of using a pair of even more 
powerful Pratt & Whitney J57 afterburning engines.  

Unfortunately, the use of the more powerful J57 engines required some 
major design changes.  Although the engines were to be placed in the 
same location as they were in the XF-88, the air intakes in the wing 
roots had to be redesigned and considerably enlarged to accommodate 
the increased air flow requirements.  Since considerably more fuel had 
to be carried, the fuselage had to be lengthened and widened, 
increasing the internal fuel capacity more than threefold (2341 versus 
734 US gallons).  Provisions were made for the fitting of a pair of 
450-gallon external tanks.  

As compared to the XF-88, the all-movable tailplane was moved almost 
to the top of the vertical tail.  The wing area was increased from 350 
to 368 square feet, obtained by increasing the chord of the inboard 
half of each wing panel.  The thickness of the wing was reduced, and 
the ailerons were moved further inboard.  

The pressurized cockpit was enclosed by a clamshell-type cockpit 
canopy, and the pilot was provided with an ejector seat.  Rear 
fuselage airbrakes and a braking parachute were fitted in order to 
enable the plane to land on shorter runways.  

Provisions were made to accommodate both types of flight refuelling 
systems in use by the USAF.  A retractable fuelling probe was to be 
mounted in front of the cockpit and a refuelling boom receptacle was 
to be installed on top of the center fuselage.  

The F-101A was to be equipped with APS-54 radar and was to be armed 
with four 20-mm cannon as well as three Falcon air-to-air missiles and 
12 unguided rockets.  For ferrying purposes, the ammunition for the 
four 20-mm cannon could be replaced by a single 226-gallon auxiliary 
fuel tank.  

The mockup was inspected in July of 1952.  On May 28, 1953, the USAF 
issued an initial contract for 39 F-101As.  No prototypes were 
specified, since the usual prototype stage was being skipped 
altogether.  

The coming of peace in Korea in July of 1953 removed some of the sense 
of urgency connected with the F-101 program.  By this time, the USAF 
had changed its mind and wanted McDonnell to redesign the aircraft so 
that it could not only carry out the originally-planned long-range 
escort mission but could also carry out nuclear strike missions.  In 
May of 1954, the Air Force got cold feet about the wisdom of going 
directly into production with the F-101A and withdrew its 
authorization to proceed with quantity production and decided to wait 
until Category II flight tests could be carried out and all the 
required changes could be made.  The completion of these tests was 
expected for sometime in March of 1955.  

The first F-101A (53-2418) was delivered in August of 1954, right on 
schedule.  After completing some ground trials in St.  Louis, it was 
shipped out to Edwards AFB.  It took off on its maiden flight on 
September 29, 1954, Robert Little being at the controls.  He reached 
Mach 0.9 at 35,000 feet.  Less than a month later, maximum speed had 
progressively been pushed to Mach 1.4.  

In the meantime, the USAF had changed its mind yet again about its 
requirements.  They now concluded that the range of the F-101A, 
impressive as it was, was not nearly large enough to be able to escort 
SAC's bombers all the way to the target.  Consequently, the Strategic 
Air Command no longer believed in the viability of the F-101 concept 
and lost any interest in the aircraft as an escort fighter.  
Ordinarily, this would have been the end of the line for the F-101A 
project, and the F-101 would have been consigned to oblivion along 
with its XF-88 predecessor.  Fortunately, the Tactical Air Command 
(TAC) saw the potential of the aircraft as a nuclear-armed 
fighter-bomber and requested that the F-101A be acquired by them under 
the aegis of Weapon System WS-105A.  Consequently, the F-101A that 
finally emerged became a hybrid aircraft, fitted with APS-54 radar and 
a MA-7 fire-control system for the air-to-air role, and a LABS 
(Low-Altitude Bombing System) for the delivery of nuclear bombs.  

On October 28, 1954, the Air Force lifted its production hold order, 
permitting McDonnell to proceed with full-scale production.  

Three other F-101As were accepted before the end of 1954.  They 
immediately began to undergo Category I flight tests.  Category II 
flight tests began in January of 1955, and at this time, problems 
appeared with engine compressor stall.  A redesign of the internal 
intake layout and engine compressor modifications cleared up these 
problems.  There was a tendency of the aircraft to pitch-up, a problem 
which was never fully corrected even after much effort.  By mid 1956 
the continued testing of the 29 F-101As which had been accepted by the 
USAF up to that time had turned up a number of structural, propulsion, 
aerodynamic, and armament problems.  

Citing numerous still-unsolved problems with the F-101, in May of 1956 
the USAF ordered that production be halted yet again.  Although the 
hold order did not last very long, F-101A production remained limited 
to only eight airplanes per month throughout most of the remainder of 
1956.  During this period, McDonnell spent most of its time in 
modifying existing F-101As rather than in building new ones.  Some 300 
USAF-recommended changes were incorporated, plus some 2000 
company-devised improvements.  

It took a long time for McDonnell to develop a cure for the pitch-up 
problem.  McDonnell fitted an active inhibitor which helped to clear 
up the pitch-up problem, at least partially.  Satisfied with the 
active inhibitor (pitch-up device) installed by McDonnell, the Air 
Force finally rescinded its May production restrictions on November 
26, 1956.  Nevertheless, the pitch-up problem was never completely 
cured, and remained a nuisance throughout the Voodoo's service life.  

The F-101A was armed with four 20-mm cannon and could carry a single 
1620 lb or 3271-lb "special store", i.e., a nuclear bomb.  The F-101As 
were equipped with the MA-7 fire control system as well with the LABS 
(Low-altitude Bombing System) for toss-release of their nuclear bombs.  
The F-101A could not carry or deliver conventional bombs.  

The first Voodoo delivered to an operational unit was a F-101A which 
reached the 27th Strategic Fighter Wing at Bergstrom AFB on May 2, 
1957.  The last of 77 F-101As was delivered on November 21, 1957.  Of 
the 77 F-101As accepted, only 50 of them actually reached operational 
units.  The rest were used for experimental and test purposes to iron 
out various bugs and never attained actual service.  

On September 25, 1958, an F-101A flew 1896 miles between Carswell AFB 
in Texas to Bermuda, completing the longest nonstop/nonrefuelled 
flight yet accomplished in a Century Series fighter.  

Once the problem with the tendency to pitch-up had been addressed by 
the installation of an active inhibitor, the F-101A established an 
excellent safety record.  In fact, the F-101A had the lowest 
first-year accident rate of any operational fighter in Air Force 
history.  

The F-101A began leaving the USAF inventory in 1965-66, when 27 of 
them were transferred to the Air National Guard.  By mid-1970, 
accidents, transfers, cannibalizations, and conversions had whittled 
down the USAF's F-101A fleet to only a couple of planes.  

The ninth F-101A (52-2426) was bailed to Pratt & Whitney to serve as a 
testbed for the more powerful J57-P-55 engines planned for the F-101B 
interceptor.  It was given the designation JF-101A and was used by 
Major Adrian E. Drew to set a new absolute world speed record of 
1207.6 mph on December 12, 1957, taking the record away from the 
British Fairey Delta FD-2.  

The first F-101A was bailed to General Electric in 1958 as a testbed 
for the J79-GE-1 turbojet.  This aircraft was test flown with two J79s 
in 1958-59 before being retired to Amarillo AFB in Texas as a ground 
maintenance trainer.  

Following their removal from active USAF service in 1965, eighteen 
ex-USAF F-101As (serial numbers 54-1445, 4119, 1452, 1455, 1457, 1461, 
1462, 1463, 1468, 1469, 19470, 1472, 1475, 1479, 1481, 1482, 1484, and 
1485) were modified by Lockheed Aircraft Service Company of Ontario, 
California to serve as unarmed reconnaissance aircraft by the Air 
National Guard.  The armament was removed and new nose cones housing 
cameras were installed.  These aircraft were redesignated RF-101G.  As 
compared to the RF-101A dedicated photo-reconnaissance version of the 
F-101A, the RF-101G had a shorter and broader nose.  Along with the 
RF-101H (an equivalent conversion of the F-101C), they served with the 
154th Tactical Reconnaissance Squadron of the Arkansas ANG, with the 
165th TRS of the Kentucky ANG, and the 192nd TRS of the Nevada ANG.  
Beginning in 1970, these aircraft were supplemented by RF-101Cs 
retired from active USAF stocks.  The last reconnaissance Voodoos were 
withdrawn from ANG service in 1979.  

Serials of F-101A: 

53-2418/2422 	McDonnell F-101A-1-MC Voodoo 
53-2423/2430 	McDonnell F-101A-5-MC Voodoo 
53-2431/2436 	McDonnell F-101A-10-MC Voodoo 
53-2437/2446 	McDonnell F-101A-15-MC Voodoo 
54-1438/1443 	McDonnell F-101A-20-MC Voodoo 
54-1444/1452 	McDonnell F-101A-25-MC Voodoo 
54-1453/1465 	McDonnell F-101A-30-MC Voodoo 
54-1466/1485 	McDonnell F-101A-35-MC Voodoo 

Specification of the F-101A: 

Two Pratt & Whitney J57-P-13 turbojets, 10,200 lb.s.t. dry and 15,000 
lb.s.t. with afterburner.  Dimensions: wingspan 39 feet 8 inches, length 
67 feet 5 inches, height 18 feet 0 inches, wing area 368 square feet.  
Maximum speed 1009 mph at 35,000 feet.  Initial climb rate 44,100 
feet/min.  Service ceiling 55,800 feet, combat ceiling 49,450 feet.  
Normal range 1900 miles, maximum range 2925 miles.  Weights: 24,970 
pounds empty, 48,120 pounds gross, 39,495 pounds combat weight, 50,000 
pounds maximum takeoff.  Maximum internal fuel load was 2341 US 
gallons.  A total of three under-fuselage drop tanks could be carried, 
bringing maximum fuel load to 3467 US gallons.  Armament consisted of 
four 20-mm Pontaic M-39 cannon in the nose with 200 rpg.  

Sources:

  McDonnell Douglas Aircraft Since 1920: Volume II, Rene J.
  Francillon, Naval Institute Press, 1990.

  The Illustrated Encyclopedia of Aircraft Armament, Bill Gunston,   
  Orion, 1988.

  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