Subject: Number Eighty-Six in the Series--North American F-86 Sabre (7 of 22)

From: [email-masked]
Date: 15 Aug 93 15:58:48 GMT

>From [email-masked]

On March 28, 1949, North American Aviation began engineering design 
work on an all-weather interceptor version of the F-86.  The project 
was known as NA-164 by the company.  The USAF showed immediate 
interest in the project, and on April 7, 1949 the company felt 
sufficiently confident that they began work on a production version, 
which was known as the NA-165.  

Up to that time, all-weather jet interceptors had always been 
two-seaters, and the NA-164/165 was the first attempt to build a 
single-seat all-weather jet interceptor.  An on-board radar-guided 
intercept system would provide for the all-weather capability, and an 
afterburning jet engine would be used to provide the extra boost 
needed to reach high speed and high altitude in a hurry, an essential 
feature for an interceptor.  The omission of the second seat made for 
a simpler adaptation of the existing Sabre airframe.  However, the 
choice of a single-seat format for an interceptor required 
sophisticated electronic systems to replace the second crew member.  

An afterburning General Electric J47-GE-17 turbojet was selected as 
the powerplant, and was provided with an electronically- controlled 
fuel scheduling system which was designed to relieve the pilot of the 
tedious task of having to watch the engine behavior constantly.  A 
single throttle lever control worked through an electronic fuel 
selector which determined the amount of fuel to be fed to the engine 
and correlated the entire engine and afterburner behavior for optimal 
efficiency.  In the promotional literature of the day, this engine was 
referred to as a "blowtorch with a brain".  

An AN/APG-36 search radar was to be carried in the nose.  The nose air 
intake was lowered and reshaped to make space above it for a 30-inch 
dielectric radome covering the 18-inch antenna of the search radar.  

Plans were made for the armament to consist of a battery of 
twenty-four 2.75-inch "Mighty Mouse" unguided rockets, all mounted in 
a retractable tray in the aircraft's belly.  The use of an all-rocket 
armament was quite innovative for the time, although a more 
conventional 20-mm cannon installation was studied as a standby plan.  

The rearward-sliding canopy of the F-86A was replaced by a clamshell 
canopy hinged at the rear.  It was anticipated that the clamshell 
canopy would make for easier and safer ejection in the event of an 
emergency.  The aircraft was to be fitted with an all-flying 
horizontal tail, and the controls were to be completely hydraulic.  

In February 1950, the rocket armament was selected and all plans for 
the standby 20-mm cannon were dropped.  

A Letter Contract for two NA-164 aircraft and 122 NA-165 aircraft was 
made out on October 7, 1949.  The designation YF-86D was applied to 
the two NA-164 aircraft, F-86D to the NA-165 aircraft.  The 
announcement of the first successful USSR atomic bomb test a short 
while earlier gave a certain sense of urgency to the F-86D project.  A 
formal contract was approved on June 2, 1950, with 31 more examples 
being added to the order to bring the total to 153.  

Since the NA-164/165 was a substantially new aircraft with only 25 
percent commonality with the original F-86A, the USAF decided to give 
the new interceptor a new F-number and assigned it the designation 
F-95.  However, for political reasons the designation was changed back 
to F-86D on July 24, 1950.  The reasons for the change are sort of 
murky.  North American company officials explained that the reason for 
the designation change was that separate appropriations must be made 
by Congress to allot funds for "new" types of aircraft, but 
"developments" of existing types come under another budget category, 
making the F-86D a much easier "sell" to Congress than the F-95A.  
However, the USAF claimed that that the reason for the change was the 
fact that a contractor could justify larger unit costs for a "new" 
aircraft than it could for a "development" of an existing one.  Even 
though the USAF initially had agreed that the F-86D was substantially 
a "new" aircraft and designated it F-95A, in order to save the 
taxpayers some money they convinced North American management to agree 
that the plane was simply a "logical extension" of the existing F-86 
and the designation was changed back to F-86D.  

Responsibility for the electronic fire control system was assigned to 
the Hughes Aircraft Corporation.  On November 18, 1949, the Hughes 
company proposed that the system be designed so that the rocket attack 
on the enemy aircraft be made from a lead collision course instead of 
from the traditional tail pursuit curve.  Hughes evolved the E-4 
system for this purpose.  Until the 250-kW E-4 was available, the less 
capable E-3 50-kw system would be fitted to the first 37 production 
F-86D aircraft.  

The first NA-164 rolled out of the NAA plant in September of 1949.  At 
that time, it was still known as the YF-95A, and was so labeled on its 
nose.  Oddly enough, the two YF-95A/YF-86D prototypes had serials 
numbered after the beginning of the production run (the YF-95A had 
serials 50-577/578, and production F-86D's began with serial number 
50-455).  

Neither the rocket armament nor the fire control system were yet 
available, and in order not to delay testing both prototypes were 
initially delivered and flown without them.  In addition, conventional 
F-86A controls were fitted, and the sliding canopy and V-shaped 
windscreeen of the F-86A were retained.  An early version of the 
afterburning J47-GE-17 engine was fitted, limited to 5000 lb.st.  dry 
and 6650 lb.st.  with afterburning.  

YF-86D 50-577 went by truck to Muroc on November 28, 1949, The first 
flight was made on December 27, 1949, the redoubtable George Welch 
being at the controls.  Throughout 1950, North American test pilots 
made some 74 flights to evaluate engine electronic controls and to 
check out the function of the afterburner.  

The prototype Hughes E-3 fire-control system was received at NAA on 
May 26, 1950 and was installed in the second YF-86D (50-578) and 
tested during September.  On October 17, 1950, this aircraft went to 
Hughes for two years of development testing.  

The retractable rocket pack with twenty-four 2.75-inch "Mighty Mouse" 
FFAR (Folding-Fin Aircraft Rockets) rockets was fitted to YF-86D 
50-577 which went to Inyokern, the Navy's rocket range at China Lake, 
California for firing tests.  The 1.75-inch rocket had a 7.55-pound 
explosive warhead, a velocity of 2500 feet/second at burnout, and a 
range of 4500 yards.  First trials were carried out in February of 
1951.  The launcher took only a half-second to extend, and the FFARs 
could be fired in groups or in salvo from the launcher.  

The pressure of the Korean War led to fears that a Soviet attack on 
the US mainland could come at any time, and orders for the F-86D were 
stepped up.  An order for 188 F-86D-20-NAs under the NAA number NA-177 
was approved on April 11, 1951.  Another contract for 638 F-86D-25 
through D-35 aircraft was approved on July 18, 1951, the company 
designation for these aircraft being NA-173.  A total of 979 
production F-86Ds were now on order.  

The first F-86D-1-NA (50-455) was delivered to the USAF in March of 
1951.  This aircraft had the production configuration--with clamshell 
canopy, increased vertical tail surface area, and the all-flying 
horizontal tail which had been lowered slightly.  

The all-flying horizontal tail had an artificial feel for the pilot.  
It had more positive longitudinal control than the F-86A's tail, 
eliminating the phenomenon of control reversal at high subsonic 
speeds.  However, the all-flying tail took a bit of getting used to.  
It was very sensitive, and when a pilot was flying at high speeds at 
low altitudes he could inadvertently induce a violent oscillating 
pitching maneuver.  However, the pitching could be halted by the pilot 
simply releasing the controls.  Some system changes helped to reduce 
this problem, but the F-86D always required careful piloting 
throughout its entire career.  

The F-86D-1-NA had an empty weight of 13,677 pounds and a combat 
weight of 16,292 pounds.  It had a top speed of 692 mph at sea level 
and an initial climb rate of 12,200 feet per minute.  This was less 
than the 707 mph agreed to at the time of the contract in June of 
1950.  Nevertheless, the F-86D-1 was quite a bit faster than the 
contemporary Northrop F-89C Scorpion (650 mph) and the Lockheed F-94C 
Starfire (640 mph).  Consequently, the F-86D was chosen for two-thirds 
of the Air Defense Command's wings, and became the dominant ADC 
interceptor during the late 1950s.  

In the meantime, F-86D-1-NA acceptances were agonizingly slow because 
of delays in delivery of the Hughes E-3 fire control system.  The last 
F-86D-1 was not delivered to the USAF until October of 1952, three 
years after the original letter contract had been issued.  

The first production Hughes E-4 fire control system was received in 
December 1951, nearly three months late.  The first few examples of 
the E-4 had extremely poor quality control, with serious problems like 
incorrect wiring, wrong vacuum tubes, loose hardware, and the like.  
It was not until July of 1952 that the first E-4 equipped aircraft, 
the F-86D-5-NA (serial number 50-492) was delivered for testing.  

The 26 F-86D-5-NAs were followed by 36 F-86D-10s which introduced a 
power-operated rudder without a trimtab.  The 54 F-86D-15s introduced 
single-point ground refuelling.  This completed the first (NA-165) 
contract.  

The second contract (NA-177) began with the F-86D-20-NA, which added a 
fuel filter deicing system.  188 of these were built.  

The 88 F-86D-25-NAs introduced provisions for using the 120-gallon 
drop tanks for combat missions rather than simply for ferrying.  

The F-86D-30-NA introduced an automatic approach coupler control, and 
the manually-operated rudder with trim tab reappeared.  200 were 
built.  

The F-86D-35-NA introduced omni-directional radar ranging.  350 of 
these were built, the last one rolling off the production line in 
December of 1953.  

During the early 1950s, North American Aviation was turning out F-86Ds 
at a faster rate than they could be supplied with engine controls and 
electronic equipment.  At one time during the winter of 1952-53 there 
were no less than 320 F-86Ds parked outside the factory at Inglewood 
waiting for various electronic systems such as radar, E-4 fire control 
systems, autopilots, or engine controls.  Deliveries were eventually 
made of the electronic equipment and the F-86Ds eventually moved off 
the strip outside the Inglewood factory and out to squadron service.  
All the D-15s were delivered by March of 1953, and the D-20s, 25s and 
30s were delivered to the USAF by June of 1953.  

The 97 production F-86D-35-NA aircraft had an afterburner fitted with 
a new fuel flow amplifier and an inner ceramic liner of the exhaust to 
provide for better protection against excess heat.  

The USAF was anxious to show off its hot new interceptor to the 
public.  On November 18, 1952, F-86D-20-NA serial number 51-2945 set a 
new world's air apeed record of 698.505 mph.  The record-setting plane 
was flown by Captain J. Slade Nash over a 3-km course at the Salton 
Sea in California at a height of 125 feet.  This record was broken on 
July 16, 1953 by Lt. Col. William Barnes flying the first 
F-86D-35-NA (51-6145) over the same Salton Sea course, averaging 
715.697 mph.  

The advanced performance of the F-86D won it two more contracts.  The 
first of these new contracts, the NA-190, was approved on March 6, 
1952 and called for 901 F-86D-40 to -50 aircraft.  

The 300 F-86D-40-NAs were powered by the J47-GE-17B of 5425 lb.st.  
dry and 6500 lb.st. with afterburner.  They had a new glide path 
indicator and had an exhaust temperature gauge added to the instrument 
panel.  

Long landing runs had been a problem for the F-86D ever since its 
introduction, and a 15.6-foot ribbon drag parachute was tested on 
F-86D-15-NA serial number 50-544.  This reduced the landing roll from 
2550 feet to 1600 feet.  The success of this installation led to the 
installation of drag parachutes to all production aircraft from 
F-86D-45-NA onward.  The first D-45 appeared in April 1954.  The D-45s 
could be distinguished from their predecessors by the presence of the 
braking parachute housing with a straight fairing immediately above 
the exhaust tailpipe which replaced the curved fairing of previous 
blocks.  

The first 238 D-45s continued with the J47-GE-17B turbojet, but the 
remaining F-86Ds (52-4136 and subsequent) completed from July 1954 
onward had the J47-GE-33 with a dry thrust of 5500 pounds and 7650 
pounds with afterburner.  For a brief time, the version of the F-86D 
with the -33 engine was known as F-86G, but the designation was soon 
changed back to F-86D.  The main effect of the more powerful engine 
was an improvement in speed at 40,000 feet from 612 to 616 mph.  
Maximum sea level speed was 693 mph, service ceiling was 49,600 feet, 
and initial climb rate was 12,000 feet per minute.  

The 301 F-86D-50-NAs rounded out the NA-190 contract.  

The last production order was placed on June 12, 1953 for 624 
F-86D-55s and -60s.  These bore the company designation of NA-201.  
They were all quite similar to each other.  The last F-86D-60-NA, 
53-4090, was accepted in September 1955.  At that time the ADC had 
twenty F-86D wings.  

The F-86D was a bit of a handfull for a single pilot, and required 
more pilot training than any other USAF aircraft, including the 
six-engined B-47.  Most of the training took place at Perrin AFB in 
Texas.  Pilot trainees spent a lot of time in ground based flight 
simulators that had a replica of a cockpit duplicating F-86D controls.  
Flight training included the firing of rockets at targets towed behind 
B-45 bombers.  

By the time that late 1953 rolled around, there was a profusion of 
different production blocks of F-86Ds in service, all of them quite 
different from each other and requiring different sets of spare parts, 
different instruction manuals, and different maintenance procedures.  
This made for a maintenance and repair nightmare.  In order to make 
the various production blocks of the F-86D standard throughout the 
USAF, a decision was made in late 1953 to withdraw all F-86Ds from 
combat units in stages and subject them all to upgrades so that there 
would be a more-or-less "standard" F-86 out there in the field, making 
maintenance and repair much less of a headache.  One by one, as 
maintenance became due, these F-86Ds were taken out of service, 
returned to maintenance depots or to the North American factory, and 
subjected to upgrades such as the installation of current electronics 
or the provision of braking parachutes.  By September 1955, the 
upgrade program was completed.  

In a typical intercept mission, the F-86D's AN/APG-37 radar searched 
the sky in a forward direction, sweeping back and forth and up and 
down in a 3.5-second cycle.  Targets could be located up to 30 miles 
away.  When the target showed up as a blip on the pilot's radar scope, 
he locked the radar onto the target and the AN/APA-84 computer 
determined a lead collision course.  The pilot flew this course by 
keeping the steering dot on his scope inside a reference circle.  When 
the automatic tracking system indicated that there were only 20 
seconds to go, the pilot steered more precisely to keep the dot in a 
smaller circle.  The pilot chose whether to fire 6, 12, or all 24 of 
his rockets, and pressed the trigger.  However, the actual firing 
instant was determined by the computer, not by the pilot, and when the 
computer deemed the range to be right, the rocket pack was extended 
and the rockets were fired.  The range at which the computer fired the 
rockets at the target was typically about 500 yards.  It took a 
half-second for the pack to lower, and only a fifth of a second to 
fire all 24 rockets.  After firing, the rockets fanned out in a 
predetermined pattern reminiscent of a shotgun blast.  When the last 
rocket was away, the pack automatically retracted back into the 
fuselage belly, and an "8" appeared on the pilot's scope, warning him 
that the target was only 260 yards ahead and that he had better break 
away.  It was thought that the lead collision course attack would 
expose the F-86D to enemy defensive fire for the minimum amount of 
time, and the "shotgun" effect of the rocket pattern would ensure a 
high probability of a kill.  

If, for some reason, the E-4 fire control system went down, there was 
a stand-by optical lead computing sight provided.  

The F-86Ds rockets were meant for use against bombers, not fighters.  
If confronted by enemy fighters, the tactic was for the F-86D to turn 
towards its attackers, then use its superior speed to get the heck out 
of there.  

In 1955, an F-86D-60-NA (serial number 53-4061) was fitted with 
underwing fixtures for four GAR-1B Falcon radar-homing missiles.  
However, the Falcon missile never became standard armament for the 
F-86D.  

In the late 1950s, the F-86D served as the main air defense weapon 
against Soviet bomber attacks.  In retrospect, the Soviet bomber 
threat was grossly exaggerated, but it cannot be denied that the 
presence of the F-86D interceptor and its F-94 and F-89 stablemates 
was an important deterrent.  The F-86D served with the following 
Fighter-Interceptor Wings: 

	1st (27th 48th, and 49th Squadrons) 
	14th (37th, 48th and 49th Squadrons) 
	15th 
	33rd 
	35th (39th 40th, 41st Squadrons) 
	40th 
	51st (16th, 25th and 39th Squadrons) 
	52nd (2nd, 4th, and 5th Squadrons) 
	53rd (13th, 14th and 15th Squadrons) 
	54th (42nd, 56th and 57th Squadrons) 
	84th (496th, 497th and 498th Squadrons) 
	86th (525th, 526th and 527th Squadrons) 
	325th (317th, 318th and 319th Squadrons) 
	326th (320th, 321th and 322nd Squadrons) 
	327th (323rd, 324th and 325th Squadrons) 
	328th (326th, 327th and 329th Squadrons) 
	329th (330th, 331st and 332nd Squadrons) 
	337th (312th and 460th Squadrons) 
	355th (354th and 469th Squadrons) 

All of these outfits served in the United States, with the exception 
of the 4th, 40th, and 41st Squadrons, which served in Japan for a 
brief period.  

The following Air National Guard Squadrons also received F-86Ds: 111, 
120, 122, 125, 159, 173, 181, 185, 196, and 198.  

Many F-86Ds were later upgraded to F-86L configuration.  The F-86L 
introduced the capability of working in conjunction with the 
Semi-Automatic Ground Environment (SAGE) computerized 
ground-controlled intercept system.  The F-86L will be described in 
more detail in a later post.  

So far as I am aware, the F-86D never fired a single shot in anger 
while serving with the USAF.  Perhaps that fact alone is a testimony 
to its effectiveness as a deterrent.  

Throughout much of the 1950s, the E-4 fire control system of the F-86D 
was considered too sensitive for export to foreign nations.  A 
simplified version, known as the F-86K, was delivered in its stead.  
[The F-86K shall be described in more detail in a later post]. It was 
not until 1958 that it was deemed safe to export the F-86D overseas.  
By that time, the F-86D was beginning to be replaced in USAF service 
by supersonic types such as the Convair F-102A Delta Dagger and the 
McDonnell F-101B Voodoo, and ex-USAF F-86Ds were now freed up for 
export to Allied nations.  

56 ex-USAF F-86Ds went to the Royal Danish Air Force, and they 
equipped Nos. 723, 726 and 728 Squadrons which operated them until 
1966.  

106 ex-USAF F-86Ds were supplied to the Japanese Air Self Defense 
Force, equipping the 101st, 102nd, and 105th Squadrons of the 3rd 
Wing.  These F-86Ds were taken out of service in 1967.  

The Republic of Korea got sufficient numbers of F-86Ds to equip two 
interceptor wings.  

The Chinese Nationalist Air Force obtained enough F-86Ds to equip one 
all-weather interceptor squadron.  

Eighteen F-86Ds were delivered to the Philippine Air Force under the 
provisions of the MDAP.  

Fifty F-86Ds were delivered to the Royal Hellenic Air Force of Greece 
under the MDAP.  And, of course, an equal number of F-86Ds had to be 
delivered to the Turkish air force, the Turk Hava Kuvvetleri.  
Whenever you deliver a combat aircraft to Turkey, you have to deliver 
one to Greece, and vice-versa.  

The Yugoslavian air force, the Jugoslovensko Ratno Vazduhoplovstvo, 
obtained 130 F-86Ds.  Deliveries of US combat aircraft to what was 
obstensibly a Communist country caused a lot of political controversy 
in the USA.  For a time, these F-86Ds served in Yugoslavia alongside 
the Soviet-supplied MiG-21, one of the few situations where Western 
and Soviet-bloc aircraft served side-by-side.  

F-86D-40-NA serial number 52-3863 is on display at the Wright 
Patterson Air Force Base Museum.  

Specification of the F-86D-40-NA; 

One General Electric J47-GE-33, rated at 5500 lb.st.  dry and 7650 
lb.st. with afterburner.  Maximum speed: 693 mph at sea level, 616 mph 
at 40,000 feet.  Tactical radius: 270 miles at 550 mph.  Ferry range: 
769 miles (two 120 US gallon underwing tanks).  Initial climb rate: 
12,000 feet per minute.  an altitude of 40,000 feet could be reached 
in 7.2 minutes.  Service ceiling: 49,600 feet.  Takeoff distance to 
clear 50-foot obstacle: 3600 feet.  Weights: 13,498 pounds empty, 
18,160 pounds loaded, 19,952 pounds maximum.  Dimensions: wingspan 37 
feet 1 1/2 inches, length 40 feet 3 1/4 inches, height 15 feet 0 
inches, wing area 287.9 square feet.  

Serials of the F-86D: 

50-455/491 	North American F-86D-1-NA Sabre 
50-492/517 	North American F-86D-5-NA Sabre 
50-518/553 	North American F-86D-10-NA Sabre 
50-554/576 	North American F-86D-15-NA Sabre 
50-577/578 	North American YF-86D-NA Sabre 
50-704/734 	North American F-86D-15-NA Sabre 
51-2944/3131 	North American F-86D-20-NA Sabre 
51-5857/5944 	North American F-86D-25-NA Sabre 
51-5945/6144 	North American F-86D-30-NA Sabre 
51-6145/6262 	North American F-86D-35-NA Sabre 
51-8274/8505 	North American F-86D-35-NA Sabre 
52-3598/3897 	North American F-86D-40-NA Sabre 
52-3898/4197 	North American F-86D-45-NA Sabre 
52-4198/4304 	North American F-86D-50-NA Sabre 
52-9983/10176 	North American F-86D-50-NA Sabre 
53-557/781 	North American F-86D-55-NA Sabre 
53-782/1071 	North American F-86D-60-NA Sabre 
53-3675/3710 	North American F-86D-60-NA Sabre 
53-4018/4090 	North American F-86D-60-NA Sabre 

Sources:

  F-86 Sabre in Action, Larry Davis, Squadron/Signal Publications, 1992.

  The North American Sabre, Ray Wagner, MacDonald, 1963.

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

  The World Guide to Combat Planes, William Green, MacDonald, 1966.

  The World's Fighting Planes, William Green, Doubleday, 1964.

  Flash of the Sabre, Jack Dean, Wings Vol 22, No 5, 1992.

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