Northrop YF-23

Twins See Less

Why the YF-23 never go into production?

The YF-23 was a finalist in the USAF’s Advanced Tactical Fighter (ATF) competition, battling the Lockheed YF-22 for a production contract.

Two YF-23 prototypes were built, nicknamed “Black Widow II” 800 PAV-2 and “Gray Ghost” 801 PAV-1.

In the 1980s, the USAF began looking for a replacement for its fighter aircraft and several companies submitted design proposals; the USAF selected proposals from Northrop and Lockheed. Northrop teamed with McDonnell Douglas to develop the YF-23, while Lockheed, Boeing and General Dynamics developed the YF-22.

Of the two aircraft built, the first YF-23 (PAV-1) was fitted with Pratt & Whitney YF119 engines, while the second (PAV-2) was powered by General Electric YF120 engines.

The YF-23 was a prototype and it is composed of the parts from many different airplanes to keep the cost down.
For example, the nose gear comes from an F-15 and the main gear from F-18.

Did you know why there is an “orange label” on the nose gear?

On high-speed taxi, the nose wheel started shinning like a grocery cartwheel shimmies and the engineers came up with this little orange device.
This device effectively changes where the axle of the wheel is relative to the strut and that stopped the shimmy.
They did that in a period of less than a week and it worked superbly and it’s painted orange because it wasn’t part of the original part of the airplane.

Where did the name “Black Widow II” come from?

There was no official USAF “nickname” for the YF-23A. However, before the first flight, the Northrop YF-23A team personnel had a “Name the Plane” contest.
The name “Black Widow II” was chosen. When YF-23 first flew, it had the “Red Hourglass” symbol of the Black Widow spider painted on its underside.

But did you know why there is a Red Hourglass on the PAV-1?
When the YF-23 is at low speeds and let’s air come into the engine compartment, to cool the engine bays a little door opened mechanically.
One day one of the crew chiefs struck his head on the sharp point on the front door so we decided to make it safer by painting it red.
This whole panel became red with a big red triangle on it outlined in white and to further accentuate it,
they made another triangle pointing at it outlined, and it looked like a Red Hourglass of a black widow spider.

YF-23: designed for maximum non-detection

Northrop engineers wanted maximum non-detection at the expense of maneuverability.
This means cooling the exhaust as much as possible before it exits the plane.
Hiding it well inside the plane makes thermal detection very hard from below and the side.
The YF-23 never had thrust vectoring, you can see how far inboard the exhaust is.
It was an intentional choice to do not to add any extra weight.
The YF-22 instead has the thrust vectoring on the only pitched up and down to be light and stealthy.

Deep Enough For You

Looking at the exhaust nozzles, you’ll see that there appear to be some square type tiles back there.
These are not Space Shuttle tile these are what are called, but transpired cooling tiles.
They pump air from the compressor of the engine back through by little holes, thousands of holes, in each one of those tiles.

That hole acts to cool the metal so that the hot gases from the afterburner don’t destroy the back end of the airplane.
The reasons those tunnels or troughs are there is to provide a shield from the infrared signature from the heat signature of the airplane,
also, the V tails block that heat signature from the sides, so the airplane is a stealthy airplane both in terms
of the radar signature and it’s stealthy in terms of the thermal or infrared signature, because of these design features.

According to the test pilots, who apparently were on board from day 1, the size of the rear wing rendered the gain from thrust vectoring to be negligible.
The rear wing on the F-23 is almost the same size as the main wing of an F-15 and can turn 40 degrees.

W๐—ต๐˜† ๐˜„๐—ฎ๐˜€ ๐˜๐—ต๐—ฒ ๐—ฌ๐—™-๐Ÿฎ๐Ÿฎ ๐—ฐ๐—ต๐—ผ๐˜€๐—ฒ๐—ป ๐—ผ๐˜ƒ๐—ฒ๐—ฟ ๐˜๐—ต๐—ฒ ๐—ฌ๐—™-๐Ÿฎ๐Ÿฏ?

The YF-22 was simply more complete than the YF-23.

While the YF-23 did have advantages over the YF-22 in stealth, speed, etc.. Many of its systems were still โ€˜on the drawing boardโ€™ so to speak.
These two planes, after all, are basically flying computers. As a resultthere were tests in the trials that the F-22 completed that the F-23 didnโ€™t even attempt.

Different Twins

BTW, w๐—ต๐—ฒ๐—ป ๐˜๐—ต๐—ฒ Y๐—™-๐Ÿฎ๐Ÿฏ ๐—บ๐—ฎ๐—ฑ๐—ฒ ๐˜๐—ถ๐—ด๐—ต๐˜ ๐˜๐˜‚๐—ฟ๐—ป๐˜€, such as in combat, it created contrails in the sky.
It was like a giant โ€˜here I am – shoot me signโ€™ which really isnโ€™t what youโ€™re looking for when stealth is your whole game.

The reputation for over-promising and under-delivering on systems that had been sold by the companies in the YF-23 consortium apparently played a huge role.

Additionally, a flaw turned up in the YF-23 design during testing.
While it probably wasnโ€™t a big deal and could be overcome.
It was just another โ€˜buy it while itโ€™s broke, weโ€™ll fix it later problemโ€™ that the USAF didnโ€™t want to deal with.

Is any of this true? We donโ€™t know, since it was all supposed to be classified. So take it for what itโ€™s worth.

The YF-23A was designed to “Supercruise”, this meant that could cruise supersonic without “afterburning“.
Even though this fighter was incredible on paper, there were only two prototypes ever built and they never exceeded Mach 1.8 or 50,050 feet.

The GE engine (YF120), although more powerful, wasnโ€™t as manageable or reliable as the Pratt and Whitney. So the plane had the worst of both worlds.

Apparently, there was another problem with the design of the front windshield. It cracked on both YF-23s in flight.
On PAV-1 at Mach 0.9 and on PAV-2 at Mach 1.5 another time it cracked while just sitting in the hanger.

That may not seem like a big deal, but those were stealth designed cockpits.
The glass was special โ€˜stealthโ€™ glass and how it fits on the plane affected its radar cross-section.
Inventing a new type of glass or changing the entire cockpit is a big compromise.

The YF-23 had all kinds of problems. Especially the Gray one.
Which was the second built called Grey Ghost aka Pav2 aka Spider it has 801 painted on the rear wing.

Eight Zero One

The F-22 fired a missile, made a 9G turn and was photographed at 60 degree Angle of Attack.

By comparison, the YF-23 needed new windshields and couldnโ€™t even hold a missile in its weapons bay.
It wasnโ€™t part of the competition requirements, so the Northrup group didnโ€™t bother.
Designing a way to fire a weapon from a stealth aircraft, presents a lot of problems.
The Northrup group should have thought of this. The fact that they didnโ€™t, just shows how far behind they were.

You can see where it all went wrong for the YF-23.

One contender wasnโ€™t just completing the tasks assigned, it was exceeding them.
While the other contender was breaking down.
Sadly, just like the stereotype, the USAF had come to expect from these companies.

The YF-23 was stealthier but less agile than its competitor and in 1991 the YF-22 has announced the winner and entered production as the Lockheed Martin F-22 Raptor.

However, we certainly understand why the YF-22 was chosen.

Northrop ended its ATF program

The YF-23 prototypes were museum exhibits as of 2010, the Black Widow II (800) at the National Museum of the United States Air Force and the other one, the Grey Ghost (801) at the Western Museum of Flight (WMOF)

Source: YF-23 Test Pilot Paul Metz, Wikipedia, The National Museum of the U.S. Air Force
Photos By: United States Air Force