F-14 Questions Answered - Ask Away

[Shannow]

Originally Posted By: lubricatosaurus
The SR-71 flew in 1964. The Air Force was in contact with Kelly Johnson for years about what to do to reduce radar cross-section. Here is a summary of early 1960's implementation, not just theory: "Surfaces had to be redesigned to avoid reflecting radar signals, the engines moved to a subtler mid-wing position, and a radar-absorbing element was added to the paint. Then a full-scale model of the Blackbird was hoisted on a pylon for radar testing at a Skunk Works’ secret location in the Nevada desert. With tests carefully scheduled to avoid Soviet satellite observations, the results were impressive: The Blackbird model, more than 100 feet in length, would appear on Soviet radar as bigger than a bird but smaller than a man. The team had succeeded in reducing radar cross section by 90 percent." see https://www.lockheedmartin.com/en-us/news/features/history/blackbird.html
At least the paint maybe! Cant the tails in a little, slab-flat face the sides, bottom, etc., at least a little to help keep these things in the air against SAM and A-to-A radar.

That was tested at Area 51...the Ruskies ended up with a pretty close picture of the plan view of the plane as even 'though the model was hoisted up and down to time with satellite overflies, the shadow under it left a thermal image that gave them it's plan.

According to the book, the CIA ran the oxcart for ages before the forces got them.

 

[Astro14]

Originally Posted By: tom slick
9th stage air would certainly be hot! I guess it needs that for pressure?

I never worked on or studied the TF30, 16 stages is a lot. I did work in a shop that had both TF30 and F110 (base was transitioning from F111 to F16), the TF30 looked like a dinosaur sitting next to a F110. I later went on to work on even older dinosaurs, the T56.

I didn't see the bleed temperature in the book (I have an F-14 NATOPS collecting dust in my garage...pulled it out for this discussion...) but my memory of the bleed air temp was 1100F...so, yeah, pretty hot.

Bleed air leaks caused the loss of a couple of Tomcats early in the airplane's service. Bleed air had a fire/heat detection loop that covered the bleed air path, and was extended to cover the expansion turbine. The turbine burned up in a few airplanes, and that changed the NATOPS procedure. Primary indications of a bleed leak (warning/caution light), or two secondary indications (smell, change in pressurization, loss of temp control, etc.) and the immediate (memory) action was bleed air source to off, closing both engine bleed valves at the engines.

You then lost pressurization, cabin temperature control, external tank transfer, engine anti-ice, weapon system cooling (the AWG-9 was liquid cooled) and missile cooling on AIM-54A (also liquid cooled).

If you were high up, cabin temp was reasonable...but down low, or on a hot day, it got pretty warm under the big plexiglass canopy.

There was a ram air switch, that allowed ram air (a door in the nose would open) to provide fresh air flow, but it was ambient air, and it wasn't a huge flow. You started sweating under all the gear pretty quick...and it could get pretty miserable...

We wore a flight suit, gloves, boots, helmet, O2 mask, which left no exposed skin, really. Over all that was a G-suit, harness, and survival vest (integrated into the harness later in my career). The vest was fairly heavy, and included things like CO2 powered life vest, radio, signaling devices, knife, and in combat, pistol.

 

[Astro14]

Survival gear is a whole topic unto itself...it was good gear, and when I first started flying the airplane, it was still Vietnam-era stuff. Durable, heavy, functional. The life vest was huge when inflated, something like 45 pounds of buoyancy with two big lobes around your midsection and a big collar behind your neck....

This is good as in rough seas, floating while wearing boots, etc. is a challenge. We had to be able to swim a mile non-stop in a flight suit (this isn't easy, put on a pair of coveralls some day and start swimming...) and we had to be able to swim 75 yards non-stop wearing all our gear. So, put on bathing suit, t-shirt, flight suit, socks, boots, helmet, G-suit, and vest, jump in the pool and start swimming...there is a lot of drag, particularly from the G-suit...and the boots make it hard to get an efficient kick.

Pistol discussion is another matter...and I'm going way OT here, I suppose, but I carried my personal weapon in the Gulf War - S&W 5906, in a custom holster that the PRs made for me. Great guys. They would do anything for you if you asked nicely. In Bosnia, we got the squadron to issue the 1911, and it turns out that my custom holster worked well for the Colt. Later modifications to the vest allowed for the M-11 (Sig Sauer) to fit in the holster there.

The issued pistol in 1991 was still the S&W Chief's Special - a 5 shot .38 with a 2.5" barrel. Nice, compact, but only 5 rounds and 10 extra rounds in a bandoleer that went next to it in the vest... I was a 9mm fan for the capacity. We weren't certain how the pistol would respond in an ejection, so a lot of us, including me, carried on an empty chamber. I had two extra magazines, in a custom pouch that the PRs made for me...did I mention how great those guys were? They're really good folks.

My extra gear (above the standard stuff) was my S&W, the two spare mags, an evasion chart (waterproof map of the area showing things like vegetation for cover and food, population areas, lines of communication), two canteens and a blood chit.

Blood chits were issued, serialized (numbered), promises of US compensation for help rendered to a downed aircrew. It was written in a dozen languages, things like Arabic, Farsi, Urdu, Pashto, French, English...

If I had more room, I would have carried more on my person...but I was maxed out with the above. The ejection seat pan had more equipment, including O2 supply (for high-altitude ejection), more water, the survival raft (likely the most valuable thing for most of our flying) and a locator beacon.

The locator beacon was automatically initiated by a lanyard that was connected to the cockpit floor. Seat goes up the rail, lanyard is pulled, beacon begins broadcasting. Great for finding an incapacitated survivor...

But in combat, it's great for both sides finding a survivor, so, amidst some controversy and discussion, we disconnected the lanyard to prevent a downed aircrew from being immediately located by the Iraqis...the thinking was that you could activate the beacon on the ground if you needed it (which would only be true if you couldn't operate your survival radio from your vest, which would happen if you were injured or it was damaged). I disliked this thinking.

An uninjured survivor would be able to turn off the beacon quickly, but an injured one would not be able to signal his location. So, we have precluded Iraqis from locating us, but we have also precluded rescue from friendlies.

We lost an F/A-18 about two weeks into the war. Flown by someone that I knew pretty well, worked with, a mentor to me, and in another story, one who saved my life on a night when my Tomcat had a massive fuel leak. Great guy...named Robert John "BJ" Dwyer.

Indications were that his airplane had system problems, and then a pressurization problem. It flew into the water coming back from a combat mission over Kuwait at night. We didn't know the precise location, and we never found the wreckage.

In the aftermath, we decided to reconnect those lanyards...

 

[Astro14]

Originally Posted By: RichardH
Thanks Astro14 that's exactly what I needed. Also I think your memory is better than you give it credit for as the numbers you quote look pretty much right to me.

What you've given me is answer to the questions I asked but also enough information to get a feel for whether it's working right or not. I'm now building the aerodynamic tables from NASA-TM X-62244 figure 12 effect of direct lift control (spoilers).


The extra speed makes sense aerodynamically, but am I right to think that even +6 kts isn't the best for trap weight and therefore it counts against the idea of using DLC in the first place. Is DLC one of those things that looked like a good idea but didn't work out being used that often?

One other question; do both pairs of spoilers (inbound and outbound) control roll in the normal (non DLC) flight regime?

Thanks again
--Richard

An update to my DLC discussion. I did some reading in the NATOPS manual.

On the old DLC, the spoilers went to 3 degrees up at neutral, 9 degrees up at full "down" DLC and retracted at full "up" DLC.

The numbers are less than I remembered for that iteration. But that explains why I remember it as somewhat ineffective....

So, I suppose it depends on what you want to model, the airplane's handling pre-AFC735, an 80's version, or the updated 90's version. I liked the airplane better with mod DLC..

 

[lubricatosaurus]

Originally Posted By: RichardH

One other question; do both pairs of spoilers (inbound and outbound) control roll in the normal (non DLC) flight regime?

Page 1-100 of the F-14 flight manual

F-14 Tomcat Pilot's Flight Operating Manual Vol. 1

PLEASE NOTE: THIS IS VOLUME 1 OF 2. YOU MUST PURCHASE BOTH BOOKS TO HAVE A COMPLETE SET. Developed as both an air superiority fighter and a long-range naval interceptor, Grumman's F-14 Tomcat was the U.S. Navy's primary fighter from 1974 until 2006. Over 700 were built. The F-14 flew its first...

books.google.com

Yes, all 4 spoilers, 2 on each wing work together.
This manual is also available in Farsi, for some unknown reason.

Actually DLC was used on one airliner: Lockheed L1011 would shoot approaches at nearly zero pitch angle excursions for passenger comfort and go-around response using spoilers like the F-14. I tried to talk them into using this on the MD-11 back in the day, since it was really a NASA invention, but they preferred to have the passengers experience the joy of pitch adjustments on approach to increase the thrill factor and fill those barf bags.

 

[Astro14]

The Shah of Iran wanted the best fighter he could buy, partly to stop Foxbat overflights, so he bought the F-14.

79 were delivered. Iran stills flies them.

See my previous posts for a detailed explanation of DLC...

 

[spasm3]

Originally Posted By: Astro14
The Shah of Iran wanted the best fighter he could buy, partly to stop Foxbat overflights, so he bought the F-14.

79 were delivered. Iran stills flies them.

See my previous posts for a detailed explanation of DLC...

I understand that is why they f-14's were shredded, so that no parts could make it to them.

I wonder if Russia, made some replacement parts for them.

How much of a threat would a couple of these be to our fleet?

 

[Astro14]

That's exactly why we started shredding F-14s.

A crime really, like crushing Bugattis or Packards....beautifully built machines...bought for millions...destroyed.

The Iranian F-14s are still flying. Not all of them, but you can cannibalize and reverse engineer parts. They've managed to make new air to air missiles and they have converted a 747 into a air refueling tanker. I'm certain that other countries provided technical support in keeping the airplanes flying and developing those new capabilities.

It is still a 4th generation fighter. So, it is still a threat.

You might enjoy this article:

Persian Cats

How Iranian air crews, cut off from U.S. technical support, used the F-14 against Iraqi attackers.

www.airspacemag.com

 

[spasm3]

I'm guessing if things get ugly , that we would take them out on the ground with stealth.

 

[Astro14]

Originally Posted By: spasm3
I'm guessing if things get ugly , that we would take them out on the ground with stealth.

That would depend on how much warning we have and what we already have available if things get ugly.

It took 30 days to get the F-117s ready and in position for Desert Storm...the CVNs are already there...

There are many areas of the world where the USN really could use the F-35...or the production version of the X-47B...the stealth and range are game-changers...

 

[Win]

Are the seats adjustable? If not, how is the cockpit fitted to the aircrew? Do the stick and rudder pedals adjust to the crewmember, or is it a one size fits all?

Is it a dual control aircraft capable of being flown from either crew position?

How do you keep your feet on the rudder pedals in a high G maneuver? Are there stirrups or something to keep them firmly located? Are the rudder pedals just rudder pedals, or do they have toe brakes or other control functions? Do you work the rudder pedals, or do the flight computers take care of that?

How long can the aircrew handle being in the aircraft, before their reliability breaks down? I imagine with all the noise, no room to stretch, concentration, etc., it saps you pretty fast.

Did you ever get a few minutes to just enjoy flying the big plane, or was it all work, all the time?

 

[Jetronic]

Did you ever fly training exercises or had encounters with (that you can talk about) modern russian aircraft, so you could compare capabilities?

It's not against an F-14, but I wonder what a Flanker is capable off in the right hands if a Fulcrum apparently got the better of an F-15C during training exercises. The fulcrum being a cheaper and downsized version of a flanker so to speak..

Originally Posted By: wikipedia
The Federation of American Scientists claims the MiG-29 is equal to, or better than the F-15C in some areas such as short aerial engagements because of the Helmet Mounted Weapons Sight (HMS) and better maneuverability at slow speeds. This was demonstrated when MiG-29s of the German Air Force participated in joint DACT exercises with US fighters. The HMS was a great help, allowing the Germans to achieve a lock on any target the pilot could see within the missile field of view, including those almost 45 degrees off boresight. It was not until 2003 that the USAF and US Navy achieved Initial Operational Capability of the Joint Helmet Mounted Cueing System.


The MiG-29 got updated to the MIG-35 IIRC

 

[Astro14]

Originally Posted By: Win
Are the seats adjustable? If not, how is the cockpit fitted to the aircrew? Do the stick and rudder pedals adjust to the crewmember, or is it a one size fits all?

Is it a dual control aircraft capable of being flown from either crew position?

How do you keep your feet on the rudder pedals in a high G maneuver? Are there stirrups or something to keep them firmly located? Are the rudder pedals just rudder pedals, or do they have toe brakes or other control functions? Do you work the rudder pedals, or do the flight computers take care of that?

How long can the aircrew handle being in the aircraft, before their reliability breaks down? I imagine with all the noise, no room to stretch, concentration, etc., it saps you pretty fast.

Did you ever get a few minutes to just enjoy flying the big plane, or was it all work, all the time?

Hey Win - in order...

The seats adjust vertically for different heights. It's an ejection seat, so you can't adjust much without messing up the ejection geometry. The rudder pedals adjust for reach, so the airplane accomodates a wide range of sizes...

There is only one set of controls. Makes for an interesting first flight. First flight in the jet, for a pilot, is with an instructor pilot in the back seat. In the back seat, that instructor has two controls: intercom switch and ejection seat. The latter to be used if the former is ineffective....

That instructor pilot was the same instructor that gave the new pilot his simulator checkride. The simulator syllabus was rigorous and extensive.

The pedals are conventional airplane pedals, with toe brakes at the top...under G, your heels ride on slick, stainless steel floor tracks, so you can easily slide your feet back and forth.

The Tomcat's flight controls, when I flew it, were mechanical with computer stability agumentation. In the hands of a great pilot, it was a truly formidable fighter, able to maneuver at very low speed and very high AOA...but because it was mechanical, the pilot's skill really, really mattered. Anyone could fly the Hornet at high AOA, it was built for it and easy to handle, but the Tomcat demanded a skilled driver to perform to its best.

Even on missions, there were lots of times to enjoy the airplane. You had to stay focused, you to stay engaged, but once in a while, you could look around and enjoy the view...or have fun on the way to your assigned station...

My longest mission was a bit over 7 hours, during Desert Storm. This required multiple in flight refuelings. I was dragging at the end of it. Since you're strapped tight into an ejection seat, there isn't much wiggling around, or changing position, although I personally would mash the G-suit inflation button pretty often and "massage" my legs and lower abdomen to keep the blood flowing...

The g-suit was part of the long list of gear I mentioned above...it was precisely fitted to each pilot/RIO. Like a pair of high pants, it came up to just under your ribcage, with openings around your hips and knees. It was pressurized proportional to g-force on the plane, and inflated to pressurize your lower legs, thighs, and lower abdomen. That inflation forced the blood back up into your torso during high-G maneuvers and allowed your heart to continue providing blood to your brain. Described here:

g-suit - Wikipedia

en.wikipedia.org

We trained in a centrifuge at up to 9 G...it takes a lot more effort than people realize to remain conscious at that G-level...google Centrifuge Training, and watch some of the videos...of guys and gals not being able to maintain the blood pressure necessary...

I loved pulling G...could do it all day, up to about 6G. It took a combination of muscle strength (we lifted weights) and aerobic capacity (we ran) to be able to raise your thoracic/blood pressure to keep the flow to your brain. Tall (like me) and low resting pressure (again like me) worked against you. The workouts and the experience in the plane made it easier...but at about 7.5G, for me, the capillaries in the back of my thighs would start to burst, I would feel tingling, and I knew that I was at the F/A-18s stress limit, or about 1.0 G over the Tomcat's stress limit...and there would be little blood spots, we called them "G-measles", on the back of my legs..

 

[Astro14]

Originally Posted By: Jetronic
Did you ever fly training exercises or had encounters with (that you can talk about) modern russian aircraft, so you could compare capabilities?

It's not against an F-14, but I wonder what a Flanker is capable off in the right hands if a Fulcrum apparently got the better of an F-15C during training exercises. The fulcrum being a cheaper and downsized version of a flanker so to speak..

Originally Posted By: wikipedia
The Federation of American Scientists claims the MiG-29 is equal to, or better than the F-15C in some areas such as short aerial engagements because of the Helmet Mounted Weapons Sight (HMS) and better maneuverability at slow speeds. This was demonstrated when MiG-29s of the German Air Force participated in joint DACT exercises with US fighters. The HMS was a great help, allowing the Germans to achieve a lock on any target the pilot could see within the missile field of view, including those almost 45 degrees off boresight. It was not until 2003 that the USAF and US Navy achieved Initial Operational Capability of the Joint Helmet Mounted Cueing System.


The MiG-29 got updated to the MIG-35 IIRC

Really a question of the skill of the driver...and weapons system configuration...

The MiG-29 was developed at the same time as the SU-27. They weren't related in design, just in developmental timing. They represented the state of the art at their design bureaus.

Both have formidable maneuvering capability, but the MiG is small, with limited fuel and designed for short range point defense. It also has some very interesting short-field and unprepared field capability.

That's all I can really say..

 

[lubricatosaurus]

Originally Posted By: spasm3
I'm guessing if things get ugly , that we would take them out on the ground with stealth.

I'd be in favor of sending 1 JASSM after each Iranian F-14 (all dumped out the back of a C-5B halfway between Oman & India) to end this craziness once and for all. Those things can't be touched at night by air defenses.

 

[lubricatosaurus]

Or, in true justice fashion, have the JASSMs dropped by a few F-14s!

JASSMs are carried by the smaller F-16 now so size is not the issue, even with the JASSM-ER.
I gotta read the Smithsonian Air&Space article on Persian Cats to try to figure out why the U.S. let the hostile Iranians keep the Tomcats when our original deal was with the Shah.

F-14 Handling and Departure Resistance: Did the F-14 have a bad Dutch Roll mode? I understand the F-18 lost a few airframes due to a Dutch Roll departure condition known as Falling Leaf Mode. They never mentioned that in the '80s when I was at McDonnell-Douglas (F-18) as a young co-op intern, and I know they never originally were smart enough to see it happening back then.

 

[Jetronic]

Originally Posted By: Astro14

Really a question of the skill of the driver...and weapons system configuration...

The MiG-29 was developed at the same time as the SU-27. They weren't related in design, just in developmental timing. They represented the state of the art at their design bureas.

Both have formidable maneuvering capability, but the MiG is small, with limited fuel and designed for short range point defense. It also has some very interesting short-field and unprepared field capability.

That's all I can really say...

yes, the relationship is that the original spec got split into a cheaper point defense fighter and a heavier true air superiority fighter. I hoped you might have flown with/against them in some exercise (australia etc)as I firmly believe that training of the crew far outweighs the plane capabilities.

 

[lubricatosaurus]

Astro, refueling on the hose-drogue, did you hit wingtip vortices?
Noticed it on https://bobistheoilguy.com/forums/threads/kc-46a-tanker.242961/#post-3877183

 

[Astro14]

Originally Posted By: lubricatosaurus

Astro, refueling on the hose-drogue, did you hit wingtip vortices?

You do hit the wingtip vortex.

The worst was the UK VC-10, which had the wing refueling pod near the tip....putting the receiver right in the middle of the vortex.

Vortex could be mildly annoying...or downright rough with severe roll. Once you're in the basket, you can move out of the way. It you've got to get in first. And it's not easy. You fly the airplane in formation with the tanker, and the probe has to be aligned vertically and horizontally as you close at 2-3 KTS with the basket.

Now, that [censored] basket moves in response to tanker movement, or turbulence, or in the bow wave off the Tomcat's nose. And it isn't always predicable. And from the pilot's seat, the probe is off to the right, like a passenger side mirror, but you have to look forward at the tanker to keep your position, so it's a pain to see the probe and basket out of the corner of your eye. A good RIO is very helpful here...

Sweetest tanker was the KC-10. Nice big basket in the smooth air beneath the jet...and lots and lots of off-load....

The KC-135 was a PITA. Tanked hundreds of time during desert storm...still hated it. The basket, or either knuckle, was a jet breaker. Mis-contact the basket and it could hit the jet with anything from mild to severe damage. You had to put a kink in the 9 foot hose connecting the basket to the boom. That meant perfect alignment, then move the basket forward about a foot. Less, you might disconnect, more, you get an unmanageable loop.

I generally took the basket down and left, to keep the loop in the hose up and to the right of the probe...away from the nose, and canopy, of my airplane.

We had to use AB to plug in the -A model because of all the drag with added weapons. Also, an engine feature called MCB, mid-compression bypass, opened with probe extension. By dumping 7th stage bleed air, the engine stall margin was improved, at the cost of 3,000# of thrust per engine.

The probe created turbulence down the right side of the airplane that could cause engine issues. Actually, it was mostly the probe door that caused it. You'll often see F-14s with the doors removed, but that's because the KC-135 was so unforgiving, that doors were often damaged, and you don't want door bits going down the engine.

Even with MCB open, TF-30 engine stalls were not uncommon...and it was always the starboard engine...always...because it was operating in AB, the throttles were constantly moving to maintain position, and it was eating turbulent flow from the probe door...

Cheers,
Astro

 

[Astro14]

Originally Posted By: lubricatosaurus
Or, in true justice fashion, have the JASSMs dropped by a few F-14s! /forums/graemlins/cheers3.gif
JASSMs are carried by the smaller F-16 now so size is not the issue, even with the JASSM-ER.
I gotta read the Smithsonian Air&Space article on Persian Cats to try to figure out why the U.S. let the hostile Iranians keep the Tomcats when our original deal was with the Shah.

F-14 Handling and Departure Resistance: Did the F-14 have a bad Dutch Roll mode? I understand the F-18 lost a few airframes due to a Dutch Roll departure condition known as Falling Leaf Mode. They never mentioned that in the '80s when I was at McDonnell-Douglas (F-18) as a young co-op intern, and I know they never originally were smart enough to see it happening back then.

Falling leaf mode was no joke. We lost a few Hornets to that...and the boldface (immediate response memory items) addressed it in departure recovery...

The F-14 had wing rock. It would oscillate in roll above about 20 AOA. The longer you stayed there, the worse it got. It had a fair amount of adverse yaw at that AOA as well, which caused proverse roll, meaning that the airplane would roll opposite your stick command.

You learned to fly with rudders at high AOA... Or to use the reversal to your advantage...