Does anyone know of a kit of the ill-fated, Republic Aviation XF-103?
Republic named their aircraft with a "thunder" in them -- hence the
Thunderbolt, Thunderjet, and Thunderchief -- at RAC (Republic Aircraft
Corporation, but we employees called it "Revolting Aggravation Corporation)
the XF-103 was known as the "Thunder-Blunder." Aptly named. Worst aircraft
that never flew in the Century series. Monumental goof all around, which is
why it was kept secret so long. Now almost 50 years later, having worked on
this outrageous aircraft, I would love to build a model of it -- any kits
Sure does. Looks correct. Of course, the blurb talks about "heat-seared
titanium finish..." Striclty artists imagination. Never even got even
close to that far. The only thing that was built was a full-sized mockup.
Very impressive, but hardly flyable. The only thing that got singed on
that sucker was the American public. Alexander Kartvelli was a great
designer (P-35, P47, F84, F105) -- but when he got to the Thunder-Blunder
he was pushing 80 and (from the looks of it) senility.
The aircraft was intended to be a Mach-3 +, high-altitude
interceptor. Conceived at a time when the threat was from very high
altitude subsonic bombers. The blunder was armed only with missiles -- no
gun. Its shape was determined by streamlining concepts that preceded an
understanding of the area rule. Stricly bullet shaped. There was no
cockpit -- only a periscope -- but that was in the days when some AF types
were thinking of doing away with pilots altogether. Ejection would have
been downwards, past the humongous inlet -- roughly the size of a garage
door. We had cartoons circulating around showing the XF103 being used to
clean the runway -- so huge that inlet was.
The most amazing thing about this mother was the power plant.
It started out in the flight regime as a more-or-less conventional turbojet
engine with afterburner. At a critical speed and altitude, huge doors in
the internal ductwork before and after the turboject moved so as to bypass
the air around the turbo, converting the afterburner into a pure ramjet.
While that was going on, a good dozen hydraulic, electrical, pneumatic, and
other systems had to shifted from high-pressure turbine bleed air to low
pressure bleed air -- not to mention all the while trying to prevent the
internal shock wave from buzzing around and destroying the aircraft. Some
of the guys circulated a classified cartoon showing the first test flight of
the "Blunder" -- with Republic's chief test pilot chained in to the cockpit
and Kartvelli keeping him there by brandishing a vicious looking pistol in
It was mercifully killed in time, but after a $billion or so in
1957 dollars. But DoD and Republic proclaimed the "titanium technology
research project" a resounding success. Massive layoffs followed the
contract cancellation -- I was lucky and found a home on the F105 project.
An aircraft of which all of us former "Republicans" were justifiably proud.
What pic of the XF-103 are you comparing the Orbital Interceptor to?
That kit is actually a re-pop of Aurora's Russian Nuclear Powered Bomber
& is actually based on the Myasischev M-52. I don't see the heavy
I have , actually -- twelve of them -- but not about the Thunder-Blunder.
I was too low down in the food chain to have a lot juicy information --
just the stuff that circulated at mach 4+ around the engineering department.
Enough for a story (see below) but too thin for a book. Also, I've never
been quite sure about when the secrecy was lifted -- if ever. Embarrassing
stuff like that is often kept secret until all participants are long dead --
maybe my next correspondance will be from Levenworth.
Keep us posted!
Okay -- here's the entire story of the ill-fated mother-f. From what I see
of the pics of the model (thanks guys for the URL -- have to make that my
next project). it is pretty accurate.
Republic Aviation was my first job after graduating (1956) with a
degree in Physics from CCNY. I had a wife and newborn child to support
and the $2800 a year I earned as an electronics tech at Columbia
Presbyterian Medical Center wasn't going to hack it. Aircraft had been my
passion from an early age (avid model builder). I had learned a lot of
aerodynamics on my own and thermodynamics had been my best physics subject.
So it was not surprizing that I was offered a job at Republic in the
thermodynamics department. The thermo department in the aircraft business
is to inlets and engines what the aero department is to the airframe. For
supersonic aircraft, the inlet becomes as important as the engine and
together they are as important as the airframe. There was (is) a lot of
high-falutin aero-thermodynamics involved in design of inlets. In a
supersonic aircraft most of the air compression comes from the inlet, not
the compressor stages -- so much so, that you would dearly love to get rid
of the compressor and run the engine as a ramjet. In theory, it is far more
efficient. However, there are some "small" problems. The first of which
is that it is really difficult to keep a match burning in a supersonic
airstream. You have to get the internal air flow down to subsonic speeds.
This can be done by using a converging/diverging inlet. Contrary to
behavior at subsonic speeds, supersonic air passing through a converging
nozzle slows down (subsonic air speeds up as you all know) and as it slows,
the pressure is increased. The ideal, perfect, inlet would slow the air
down to mach 1 at the narrowest point, from which it would go to a diverging
nozzle to slow down even more -- and raise the pressure even higher -- so
that by the time you got to the flame holders, you had really slow air at
high pressure. That's the ideal, but nasty things like external and
internal turbulence, maneuver-induced instabilities, and a lot of other
stuff means that you can't have that ideal mach 1 transition. So you have a
transition, via a shock wave, at a slightly higher speed -- say mach 1.4 or
so. The shock wave itself acts as compressor -- the air flow is supersonic
on one side and subsonic on the other. Unfortunately, this configuration
has a nasty tendency to instability. The shock wave can bounce back and
forth -- oscillate -- in the inlet at frequencies ranging from about 2 hz to
20 hz -- in so doing, it can move back and forth inches -- and even feet.
Now think of what happens when you have a barrier (the shock wave) with 2psi
pressure on one side, and 40 or 50 psi on the other side ( a fraction of an
inch away) and that barrier is oscillating at 10 hertz though a foot or
more? The inlet, and the aircraft, is destroyed in seconds. Not nice.
This is avoided and controlled by having variable geometry inlets. Because
the geometry must change for every speed and altitude. The inlet isn't just
a pipe -- it is a dynamic thing that changes its shape all the time.
What I described above is called an "internal shock" or "fully
started" inlet. They are the most efficient, most difficult to design, and
most prone to inlet buzz. Note that the typical plug configuration of early
Soviet supersonic aircraft inlet strongly suggests that they opted for the
much simpler, external-shock or partially started inlets. By contrast,
most American aircraft use a fully-started, internal shock inlet.
The above long lesson on internal aero-thermodynamics is
probably more than most of you guys wanted to know. But it is important to
understand it in order to understand the issues that led to the XF103 and
its timely demise. If you go to the web page
you can see what is an
obviously internal shock inlet. What is not visible in the picture (and
very unlikely to be correct in the model) is the rather complicated
arrangments of plugs, doors, throats, and stuff that makes the inlet work.
Republic liked to build big aircraft. From the P35, to the P47,
to F105 (the F84 wasn't all that huge) RAC thunderships were big -- they
carried a big ordance load. Always hated by the airforce brass and loved by
the pilots who usually came home in them. The "Thud" (F105 Thunderchief)
was probably the best of the lot -- and the culmination of Republic's
fighter-bomber evolution. As an interesting side note, Alexandr Kartvelli's
aircraft looked like the man. He wasn't that tall, but he was kind of squat
and burly looking. Had a voice to match. They say that people's pets tend
to look like their owners -- well, I think aircraft tend to look a lot like
their designers. Sikorski was thin and elegant like his aircraft. Hughes
had a refined elegance (Spruce-Goose aside) that mirrored his best
racers...and the Wright brothers -- reedy thin and supple. By the way, you
should note that many American aviation pioneers have Russian names --
Severski, Piaseki, Sikorski, Kartvelli -- a few others that I can't
remember. All of them classmates from the 1912 (?) graduating class of the
St. Petersburg School of Aeronautics. Left Russia for better opportunities
in the West after the revolution.
Back to Thunder-Blunder. As I said in the earlier post, it was
conceived at a time when the most viable nuclear threat was subsonic,
high-altitude, intercontinental, manned bombers. Our entry into that arena
was the B-36. To counter the massive (non-existant) Soviet bomber threat,
we needed a high-altitude interceptor. Didn't have to fight defensive
aircraft because no fighters could fly so far (mid-air refueling was still
being perfected) -- so no air superiority issues. Big ugly bomber is bound
to be bristling with nasty machine guns and cannons -- so don't get in so
close -- stand off and lob a missile at them. Ground based missiles didn't
have either the range or accuracy -- needed a missile carrier to get them up
there. No defensive armament needed on the missile carrier if it is so
fast that it can outrun bullets. The idea, now that I think of it, must
have been inspired by the ME-263 rocket interceptor -- but writ large --
I said Mach 3+ because the target speed was classified and probably
still is. However, this was before area ruling was discovered and the only
way to achieve even modest supersonic speeds was through brute force -- lots
and lots of thrust. I don't remember the exact dimensions, but what
emerged was about 65-70 feet long (excluding the nose pitot tube) with about
a 40 or 45 foot wingspan. Little, thin, triangular wings -- practically
flat plates with barely enough room inside to put the aeleron and flap
actuators. All to be fabricated out of that wonder metal -- titanium. It
was light, it was strong, it didn't weaken (much) under extreme
temperatures -- and it was expensive to buy, and very difficult and
expensive to fabricate. I saved a hunk of that titanium. It is a small
square about 4" on a side. I've used it for almost 45 years to dress my
grindstone wheels -- barely a sign of wear. Machining had to be done in an
inert atmosphere, welding was an adventure, as was heat-treating and almost
every other aspect of fabrication. These fabrication problems alone would
have warranted calling the whole thing a research project -- but here's what
else they were trying to achieve:
1. The interceptor missile that was to be used wasn't
2. No one had ever built an operational (as contrasted to a
research prototype) ramjet.
3. Inlet aero-thermodynamics entailed a lot of witchcraft
4. We didn't really undersand inlet buzz and
prevention/correction methods were brute-force at best.
5. Operational supersonic aircraft flight had just begun --
still a lot of R&D involved.
6. Turbojet engines were puny by comparison to today's.
7. Transistors were still experimental -- aircraft avionics
relied on vaccuum tubes and electrical relays. Controls were based on
analog, not digital computers. And this was going to require some really
fancy control systems to safely manage the transition.
But these problems were minor compared to the engine problem
and the weight problem. First the weight problem. You may not think or
know this, but weight is really important in a military aircraft. You have
an aircraft whose dry weight is say, 50,000 pounds, and you knock of five or
six pounds, you'll get a nice bonus for that accomplishment. I remember
one day at Republic that one of the engineers had figured out a way to knock
off about 100 pounds from the F105 (55,000 pound aircraft) by redesign of
the bomb release/ejection mechanism: They carried him on their shoulders
around the entire engineering floor while we all cheered (this was before
Republic had won the flyoff against the North American F107). Well,
cramming in all the required electronic wizardry, the controls, and
fabrication difficulties meant that the XF-103 continued to gain weight,
week-by-week, pound-by-pound. That weight gain meant additional fuel and
more weight. It might have been partially compensated for by an increase in
thrust -- but that was where the real trouble was.
At the time, there were only a few jet engine manufacturers in
the West: G.E. was probably number one, Rolls-Royce, Westinghouse, SNECMA
(French), Fairchild, Pratt& Whitney, and last and least,
Wright-Aeronautical. They were late getting into the jet engine business --
after all, when you have only to slug it out with Pratt & Whitney for the
reciprocating engine market and you are number 2 in that business, you don't
have time to fool around with those new-fangled thingies. They had made a
few operational engines but they sure weren't the leaders like G.E. So
when DoD came up with the revolutionary idea of turbo/ram engine, Wright
jumped in, ass first, and said they could and would do it. I don't
remember the exact engine name -- I think it was called TJ-67-W-9/XRJ57-W-3
or something like that. Note that Republic cannot be given all the blame.
In military aircraft design, DoD usually specifies the engine and tells the
airframe manufacturer to build an aircraft around it. In any event, the
engine development and aircraft development are usually separate and the
aircraft manufacturer can be on wrong end of the stick with the engine
manufacturer. The best example of this is the Mustang-- it was a dog as
long as it doomed to piddling around with the puny designated Allison(?)
engine-- it became a world-beater only after it was retrofitted with the
Rolls-Royce Merlin. That was a success story -- the XF103 was the opposite
side of that engine/aircraft coin.
Week-by-week, the weight grew and week-by-week, the predicted
thrust declined. 50 pounds lost turbo thrust this week, 30 pounds lost
ramjet thrust next week, 3% fuel consumption increase the following week,
etc. etc. Sometime in 1957, I think it was, the project was renamed from
F-103 to XF-103 -- as if to tag it into the X series aircraft made it
acceptable. Security went up. Despite the fact that three-views had
appeared in Aviation week, despite the fact that the full-sized mockup had
been in open view in an unsecured hangar for months. I got caught in that
security clamp down-- a sort of Laurel and Hardy comedy act. I was showing
a new employee, who knew his math and physics, but squat about aircraft, I
was showing him around the cockpit of the mockup. Now this cockpit was up
three flights of stairs, some 30 feet off the ground -- and almost half of
that distance was aken up that by gaping maw of a barn-door sized inlet.
Anyhow, I'm sitting in the mockup's cockpit and explaining the throttle, the
afterburner detent, the transition controls, joy stick, rudder pedals,
turn-and-bank, other instrumentation, etc. We had been there about two
hours -- when all of a sudden, from below, came the fog-horn bullroarer
sound of the company security chief. "What the ---- are you doing up there?
Don't you know it is classified SECRET? you'll spend a time in jail I can
tell you!" -- and other dire threats. While we had been up there, the elves
had come and surrounded the entire mockup with curtains and signs that said
"OFF LIMITS"-- No one had bothered to look up to see that we were there --
and had been there before the curtains had come down and off limit signs put
up. As it turned out, my blessed boss saved the day. He pointed out that
the curtains had not been there before and that the entire mockup had been
in plain view for months -- including to the guy who sold greasy sandwiches
from a stand next to the left wheel -- and that both of us had the proper
clearances (they had come through the day before) and authorization to be
there. He sort of apologized and let us off with a stiff warning to be
careful in the future -- these were the days of the McCarthy insanity and if
there were Soviet agents in every government department, it figured that
there had be some in a company run by a Russian (Kartvelli) and that a
junior engineer named "Boris" was sure to be suspicious. Actually, my title
was "senior engineer", but they were free with titles at Republic and gave
them out in lieu of raises -as far as the food chain went, I was still a
pretty junior engineer.
By then, the project was no longer an attempt to build a supersonic
interceptor -- because the ICMB threat was looming on the horizon and the
entire bomber-interceptor thing began to look sillier and sillier. It had
graduated to a "titanium fabrication research project." There was some
buzz around of renaming it the "X103" as contrasted to "XF-103." The
former being an NASA (then NACA) experimental aircraft designation, whilst
the "F" made it clear that this was an AF boondoggle -- but NACA would have
none of it -- they had their own supersonic embarrassments to get over.
The thrust kept going down, the weight kept creeping up, as did the take off
run, the landing run, and the number of jato rockets that would be needed
for lift off. And with each passing week, those of us on the 103 project
kept sharpening our resumes, looking for ins to the F105 project (still
shaky, but a lot healthier) and opening channels to our colleagues down the
road at Grumman for possible jobs. Meanwhile, the classified cartoons of
the XF103 kept coming out and getting nastier and nastier. Our laison with
the engine manufacturer became ever more formal, more difficult, more
frustrating, and less informative, despite the fact that very close
cooperation for such an aircraft was more important than for any previously
conceived aircraft. The culmination came in the following conversation -- I
wasn't there (much too low on the totem pole for that) but it was widely
reported, orally, by people who had witnessed it.
Lead engineer: "We've got another 75 pound drop in take-off thrust. But
I think Wright's shading the truth. It will probably be worse than that."
Weights and Balance engineer:" Not to mention another 53 pounds take-off
weight increase this week."
Kartvelli:"What does that do to our take-off run?"
Lead Engineer: "We can manage that with more Jatos -- now that we're
going to jettison the package and stuff after use."
Weights & Balance:" We've just got to lose 300 pounds. It has to be
Structures Engineer:" Can't be done. There isn't 300 pounds to lose in
the entire 60,000 pound aircraft."
Kartvelli: "What's the projected landing run?"
Aero: "10,500 feet -- but we've got four miles of paved runway at
Kartvelli: "What's the landing run without the drag chute?"
Aero: "Ten miles --maybe twenty if you want to use the tires and brakes
Kartvelli: "What does the drag chute weigh?"
Kartvelli: "How miles of salt flats beyond the runway."
Flight Test:" Almost 40 miles."
Kartvelli: "Take out the drag chute!"
The following week I was slated to make a high-level
presentation, first to our upper management, then to a joint Wright-Republic
meeting, and then to the Air Force. The subject was to explain the "logic"
of the transition, the discovered points of contradiction that had to be
resolved, and the kind of control system that would be needed to make it
work -- if it was at all possible from a controls point of view (never mind
from the point of view of aerodynamics, thermodynamics, or sanity). I had
been preparing this presentation for several weeks --It was Friday when my
boss told me that I would not have to come in for the dry-run that
Saturday - that told me the whole story. That was the bad news. The good
news was that I had earned a berth on the F105 project.
I have never seen a project terminated so quickly. That monday,
the pink slips went out. It took only one week to get the project wrapped
up. Photography teams came in to every department. They went through your
desk and files and pulled out every sheet of paper having to do with the
103 -- including your laundry ticket and the grocery shopping list if it
happened to be on your desk. Every sheet numbered, stamped, photographed
for micro-filming, and then shredded and burned. By the end of the week
not a scrap of evidence remained. The mockup was gone. The files were
gone. The drawings were gone. The fabrication jigs were gone, as were some
8,000 of our fellow engineers and craftsmen -- all of whom had spent the
entire week assisting in the closing down. Republic collected many
millions -- or was it hundreds of millions? Billions? of dollars in
cancellation fees. The only truly legitimate part of that was the two weeks
severance pay that the engineers got and the one week that the workers got.
So what happened to the XF103? You remember the final scene in
"Raiders of the Lost Arc?" The scene were the crated arc is deposited in
some huge government warehouse among millions of similar, myserious,
indistinguishable crates. I just know that someplace, beneath some mountain
or in an abandoned salt mine -- there are thousands of file cabinets filled
with decaying micro-film, tons of oddly shaped pieces of titanium -- and in
a huge crate, or more likely, surrounded by dark blue velvet curtains
bearing the legend "RESTRICTED AREA -- SECRET- NO UNAUTHORIZED ACCESS"--
behind the velvet curtains is the XF103 mockup.