Heatblur F-14 and Forrestal Update

From the sounds of it were getting an F-14A circa 1986 (ostensibly a block ~130?). So an AN/ALR-45, PW TF-30-414A (less explodey than the earlier versions), welded wing vanes, and TARPS.

The previous incarnation of that engine has a habit of doing the explode-y part of being an engine all wrong?! Please elaborate!

The original engines in the tomcat were the TF-412As, which were more or less ripped out of the F-111B as a stop gap until a next generation engine could be developed in conjunction with the air force. (In the budgetary apocalypse of the Vietnam drawdown this was cancelled.). It was hoped the longer intake and variable inlet would solve the compressor stalls endemic to the F-111. It would not.

The maiden cruise of the Tomcat also uncovered a more alarming problem wherein a manufacturing defect in the compressor blades meant they were more brittle than specified. If uncaught, the blades would degrade, and ultimately break catastrophically, shredding the engine, and often, the second engine, resulting in loss of aircraft.

The problem was caught, the blades rebuilt and a steel jacket was made to contain the blade shedding. Additional approvements would be made to further prevent this, and alleviate compressor stalls at certain regimes (landing). These changes Mark the change between the 412 and 414. The 414A was an additional improvement.

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Aaaah, same old same old then! It’s amazing how far we’ve come with engine tech these days.

@BeachAV8R, ever experienced a compressor stall on a turbine engine?

I could type you a 10 paragragh article on the Tomcat’s Engines from Prototype F-14 to Final Incarnation.

There were More than 3 Engines used in the F-14 Airframe (If you count the prototypes)

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Please do as such if you do not feel bothered by it! Very interesting really!

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Like dis?

(my mind snapped back to this from growing up watching this special on the Carl Vinson)

Yes
but only because the bleed off valve failed (and closed) just after liftoff. It was the only time I’ve experienced it (it was exciting)


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Twin engine aircraft I hope?

Yes - and had I been a more experienced pilot at the time, I would have known that just reducing power significantly on the compressor stalling engine would have made it stop doing it. We had just picked the airplane up out of maintenance though, and when it does it, it is pretty violent surging and flames shoot out the exhaust
and I had no idea what was going on, so I shut it down and brought it around the pattern on the other engine. If I had just backed off on the throttle about 20%, it would have settled down on its own. Live and learn. :smiley:

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I’ve had experience with that - in a PT6 that came apart on me. The steel mesh cage around the turbine section caught most of the debris, but the blades still had enough momentum to punch through the mesh cage, but they bounced off the inside of the nacelle. Without the steel cage, I’ll bet some of those blades would have made it out of the engine nacelle, and into the cabin of the aircraft
 I mean, they are only whirling around out there at 38,000 RPM or something ridiculous


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Please elaborate. I seem to have missed the required reading list. Any recommendations for a nice book on the Tomcat?

That is quite a bit of damage! Do they know what caused it, I would presume uncaught cracks in the disc?

Reminds me when we got a engine with a seized bearing a while ago. Well it wasn’t seized. It had just stopped existing, when we pulled it apart the bearing rollers just kind of
 fell out. They just say there at the bottom in a sad puddle of dysfunctional material.

The rest of the engine was quite undamaged, amazing bit of engineering!

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So what HeatBlur is sayin’ is
 Dont Fly through your wingman’s jet wash
 :wink:

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And there I was believing that the PT6 was practically bulletproof. I have about 1800 hours of King Air time logged (just a fraction of what you must have I’m sure), and I never experienced the slightest bit of trouble from the engines.

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Great. You might guess my next question. If you had to buy only one. Which one would it be? :smiley:

ooh, that’s difficult.

The first book by Paul Gilcrist is a great read with bunch of great photos and even better stories. If you read a lot of US Naval History, you might recognize the name of the author, if you don’t he was a Naval Aviator in from the 50’s through the 80s. He was in the Pentagon during the F-14 acquisition and support processes. He uses his first hand knowledge, as well as a bunch of second hand stories to craft an oral history of the Tomcat through the early 90s. A lot of it is “Stories from Baseball”, but it’s all entertaining, and it offers a pretty good picture into why the F-14 never got the upgrades that were planned and why it was always making do.

The second is a technical history of the Tomcat that offers a pretty good explanation of technical systems while interspersing those with testimonials from serving Tomcat pilots. I’d honestly lean towards this one.

The third is
 I have no idea how it got published. It’s the closest thing to a NAVAIR manual I’ve seen in print (that isn’t the actual NAVAIR which is out there :kissing: :notes:) , and it was printing in like 1976. There was talk the author almost got indicted on illegal export charges. It offers a pretty good technical rundown of a 1970s vintage F-14, with some neat diagrams on what various sensors display in certain modes.

I’d go with the first if you want a better understanding on the history of the Tomcat and Tomcat community, the second if you want a history of the Tomcat and a more technical explanation. and the third if you want a high level brief on know how a Block 90 Tomcat ticks.

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Thanks a lot. They all are very tempting. Nice collection you put up there. I will have to meditate before making a decision :dizzy_face:

I love meeting Pilatus pilots that tell me they’ll never have an engine failure. Of course, statistically, they are right
but it does happen
 I sure am glad mine happened where it did (16,000’, VMC, within “gliding” distance of Nashville).

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