Sounds like you passed your Plane Captain board if you still remember the engine oil spec for the TF-30! Line Division worked hard - long hours, all weather, on the flight deck....thanks for your service, Sir!
F-14 Questions Answered - Ask Away
- Thread starter Astro14
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Sounds like you passed your Plane Captain board if you still remember the engine oil spec for the TF-30! Line Division worked hard - long hours, all weather, on the flight deck....thanks for your service, Sir!
And thank you for your service Astro. Actually, I was a jet mech/plane captain on J-52/EA-6B aircraft 71-75. It's a long story but I retired in 1992 as an Avionics Chief.
Great thread. I've enjoyed reading about your experiences. I've always thought the Tomcat was a beautiful aircraft.
In the very early 70s I rode back seat in an EA-6B from Whidbey to Miramar. I was on the ramp, polishing the canopy on my jet when an F-4 and F-14 lined up on the runway for take off. Both went to full AB and away they went. The Tomcat was long gone before the F-4 went wheels in the well. Very cool!
Great thread. I've enjoyed reading about your experiences. I've always thought the Tomcat was a beautiful aircraft.
In the very early 70s I rode back seat in an EA-6B from Whidbey to Miramar. I was on the ramp, polishing the canopy on my jet when an F-4 and F-14 lined up on the runway for take off. Both went to full AB and away they went. The Tomcat was long gone before the F-4 went wheels in the well. Very cool!
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Exactly right - good memory!
The current version is MIL-PRF-23699F. The "L" was replaced with "PRF" to indicate it was a performance specification. It now comes in three classes:
STD = Standard
C/I = Corrosion Inhibiting
HTS = High Thermal Stability
C/I is the dominate class and prevents rust in storage, while HTS is designed for advanced and future engines and is used in F-22s.
Tom NJ
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What are the differences between F14 & F15. To the casual observer they look quite similar. From what I have read(and it is limited at that) F14 and F15 were money no object planes when developed . F16 was a low cost alternative to be used over land since it had one engine. F18 was lower cost alternative to F14/F15 to be used primarily by the Navy as they navy required two engine jets. The F14 and F15 look so similar it is hard to distinguish between the two.
The high end / low end assessment is true. Beyond that. The only similarities are twin engines and twin tails and powerful radars.
They were developed at the same time, but Grumman and McDonnell weren't sharing any design details. The Eagle was designed for air superiority. The Tomcat was intended for fleet air defense - long range missions against superior numbers and bombers. The AIM-54 was key to fulfilling that requirement.
Airframe: both have variable inlets for high Mach flight, but the Eagle has an articulated forward section where the Tomcats ramps are internal. The Tomcats engines are 9 feet apart, leaving a large fuselage area which adds to lift and where weapons are carried. The Eagles engines are closer together.
The major difference is the Tomcats variable wing. They move between 20 degrees (landing and slow speed) and 68 degrees in flight and to 72 degrees while on deck to minimize parking space. The Eagles wings are conventional; fixed. The tomcat also has leading edge slats.
The Tomcat can handle carrier landings - fuselage, landing gear, hook are all far stronger than needed for runway landings. Grumman pioneered electron beam welding to make extensive use of titanium in the structure - particularly between the wing sweep pivot points.
Engines: the eagle had better engines, the TF-30 was designed for the F-111 and was intended for development only. Budget cuts kept the engine in service far longer than it should have been. Later versions of both planes got better engines, but the difference in the Tomcat was more dramatic and put it on par with the Eagles thrust/weight.
Weapons: the bigger radar in the Tomcat was designed to support the AIM-54 Phoenix - a missile with far greater range, and true multi shot capability. Both airplanes carried AIM-7 Sparrow ( radar guided medium range ) and AIM-9 (heat seeking short range) as well as 20mm M-61 cannon. Later, the Eagle got AMRAAM, which allowed multi shot.
The Tomcat was also designed to carry bombs, a capability that was used later in life, while the Eagle, in the F-15C, remained focused on air superiority. In addition, the Tomcat carried a reconnaissance pod to fly tactical reconnaissance missions.
Finally, the Tomcat is designed for a crew of two. The Eagle was designed for one.
Look at a Tomcat from above - wings forward and wings aft. Watch some video of it landing - very different machine from the Eagle...which is one of my favorite jets: elegant, clean, fast, and lethal.
They were developed at the same time, but Grumman and McDonnell weren't sharing any design details. The Eagle was designed for air superiority. The Tomcat was intended for fleet air defense - long range missions against superior numbers and bombers. The AIM-54 was key to fulfilling that requirement.
Airframe: both have variable inlets for high Mach flight, but the Eagle has an articulated forward section where the Tomcats ramps are internal. The Tomcats engines are 9 feet apart, leaving a large fuselage area which adds to lift and where weapons are carried. The Eagles engines are closer together.
The major difference is the Tomcats variable wing. They move between 20 degrees (landing and slow speed) and 68 degrees in flight and to 72 degrees while on deck to minimize parking space. The Eagles wings are conventional; fixed. The tomcat also has leading edge slats.
The Tomcat can handle carrier landings - fuselage, landing gear, hook are all far stronger than needed for runway landings. Grumman pioneered electron beam welding to make extensive use of titanium in the structure - particularly between the wing sweep pivot points.
Engines: the eagle had better engines, the TF-30 was designed for the F-111 and was intended for development only. Budget cuts kept the engine in service far longer than it should have been. Later versions of both planes got better engines, but the difference in the Tomcat was more dramatic and put it on par with the Eagles thrust/weight.
Weapons: the bigger radar in the Tomcat was designed to support the AIM-54 Phoenix - a missile with far greater range, and true multi shot capability. Both airplanes carried AIM-7 Sparrow ( radar guided medium range ) and AIM-9 (heat seeking short range) as well as 20mm M-61 cannon. Later, the Eagle got AMRAAM, which allowed multi shot.
The Tomcat was also designed to carry bombs, a capability that was used later in life, while the Eagle, in the F-15C, remained focused on air superiority. In addition, the Tomcat carried a reconnaissance pod to fly tactical reconnaissance missions.
Finally, the Tomcat is designed for a crew of two. The Eagle was designed for one.
Look at a Tomcat from above - wings forward and wings aft. Watch some video of it landing - very different machine from the Eagle...which is one of my favorite jets: elegant, clean, fast, and lethal.
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I'm resurrecting this thread to simply talk about aviation.
Not politics.
Not religion.
Not even current events, which attracts the trolls.
This is was focused on the F-14. I'll start one about the A-320.
Not politics.
Not religion.
Not even current events, which attracts the trolls.
This is was focused on the F-14. I'll start one about the A-320.
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Thanks Trajan - wanted to get back to talking about airplanes for airplanes' sake...not airplanes as an extension of political discussions...
You're welcome. It happens to be true
I've read, oh sometime in 1978, that a F-15 in full afterburner would burn through it's fuel in about 6 minutes.
How about the F-14?
I'm curious about the ejection sequence. I've read in Trotti's 'Phantom over Vietnam' that if the back seater doesn't eject, the pilot can't either. The pilot can eject the back seat, but he can't go first.
Is the F-14 similar?
I've read, oh sometime in 1978, that a F-15 in full afterburner would burn through it's fuel in about 6 minutes.
How about the F-14?
I'm curious about the ejection sequence. I've read in Trotti's 'Phantom over Vietnam' that if the back seater doesn't eject, the pilot can't either. The pilot can eject the back seat, but he can't go first.
Is the F-14 similar?
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First, the TF-30 engines used about 2,000# of fuel per minute in full AB at low altitude and high speed.
That's the worst case, fuel consumption was lower at high altitude and lower at slower speeds. It's a mass thing, the more air by mass moving through the engine, the more fuel was needed.
The F-14 held 16,200# internal fuel and could add two drop tanks of 2,000 # each, for a max total of 20,200#. So, yeah, in the worst case, full AB at low altitude and high speed, you could run yourself out of gas in minutes.
The AB Fuel pump and lines were big, like a fire hose, to pump that roughly 150 gallons per minute per engine into the AB section.
The fuel numbers were slightly worse for the F-110 equipped airplanes. up to 2,500# per minute. But the increased thrust of the F-110 meant that you needed AB less often, so the airplane had greater range and payload on most mission profiles with the more thirsty engines.
For ejection, it was pretty easy. If the Pilot pulled, both were going out. Canopy first, a few tenths of a second later, RIO and a few tenths later, pilot.
There was a command eject selector in the back. If it was forward, in PLT, then the RIO could only eject himself. If it was rearward, in MCO, then the RIO could eject both.
We always flew with it in MCO. But once in a great while, say, if you had a midshipman on a familiarization ride, we would fly with it in PLT. So that if our inexperienced passenger made a mistake, we wouldn't lose the airplane.
That's the worst case, fuel consumption was lower at high altitude and lower at slower speeds. It's a mass thing, the more air by mass moving through the engine, the more fuel was needed.
The F-14 held 16,200# internal fuel and could add two drop tanks of 2,000 # each, for a max total of 20,200#. So, yeah, in the worst case, full AB at low altitude and high speed, you could run yourself out of gas in minutes.
The AB Fuel pump and lines were big, like a fire hose, to pump that roughly 150 gallons per minute per engine into the AB section.
The fuel numbers were slightly worse for the F-110 equipped airplanes. up to 2,500# per minute. But the increased thrust of the F-110 meant that you needed AB less often, so the airplane had greater range and payload on most mission profiles with the more thirsty engines.
For ejection, it was pretty easy. If the Pilot pulled, both were going out. Canopy first, a few tenths of a second later, RIO and a few tenths later, pilot.
There was a command eject selector in the back. If it was forward, in PLT, then the RIO could only eject himself. If it was rearward, in MCO, then the RIO could eject both.
We always flew with it in MCO. But once in a great while, say, if you had a midshipman on a familiarization ride, we would fly with it in PLT. So that if our inexperienced passenger made a mistake, we wouldn't lose the airplane.
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When you slide the throttle past military does it go into afterburner or augmentor? The engines I worked on had augmentor but I wondered if the pilots called them afterburner regardless.
Can I fly it???
Augmentor is what the engineers called the afterburner on the F-110. Pilots just called it AB, or afterburner.
The throttles on the airplane moved forward to military (full RPM and U augmented thrust) where there was a stop. You could slam the throttles to that stop.
A slight move to the left (outboard) of half an inch or so, and the throttles would slide forward another two inches into afterburner range.
You could modulate the amount of afterburner. In the TF-30, there were five discreet zones of AB, and you could feel each one light with a bump in thrust. In the F-110, the AB variation was smooth, from minimum to maximum.
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I can only wish! I would love to fly one just once more. It's been seventeen years and I remember all the details....like it was yesterday....
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Thanks for sharing your stories and knowledge, very interesting reading!
I've been watching Jetstream which is a show about a group of canucks trying to become f-18 pilots. http://jetstream.madebymod7.com/demo/
Some of the dogfight training clips really show what you mean by adding energy, the speed bleeds off pretty quickly in maneuver after maneuver.
I've been watching Jetstream which is a show about a group of canucks trying to become f-18 pilots. http://jetstream.madebymod7.com/demo/
Some of the dogfight training clips really show what you mean by adding energy, the speed bleeds off pretty quickly in maneuver after maneuver.
We generally started the left engine first.
The whole normal start/preflight check sequence was long, involving tests of the air inlet control system, wingsweep and flap interlocks and flight controls.
But to start the engines was pretty straightforward: power connected, starter air connected, electric lights test, fire warning system test. Engine start switch to the engine being started (this opened a valve on the air turbine starter and began turning the engine). As the RPM advanced above 18% RPM (minimum, we generally went for the maximum that the starter air source would give us), move the throttle for that engine from cut-off to idle, watch for fuel flow (about 400#/hour flow to start), within a few seconds of fuel flow, the TIT (Turbine Inlet Temperature) should rise. If TIT was rising rapidly (hot start), or if there was no rise (wet start), or the RPM did not advance normally (hung start), then move the throttle back to cutoff and allow the starter to windmill the engine until cool/clear.
The F-110 motor was similar, except that there was a digital gauge for RPM, with an illuminated pixel for fuel-on, so you weren't counting RPM as closely. The F-110 had EGT as a gauge, not TIT, and the limits were different. The digital engine controls on that engine made it more reliable on start than the hydro pneumatic TF-30 engine controls.
Once the left engine was running, you would crank the right, engage the bi-directional hydraulic pump, and stop cranking the right. As the engine wound down, observe that the BiDi picked up the right engine hydraulic system pressure, then cut the BiDi off to make sure that the selector switch for it worked*.
Then start the right engine as the left.
*There were two hydraulic systems, the left engine powered the combined system, which included landing gear, brakes, refueling probe, AICS, wingsweep and flight controls, and the right engine powered the flight hydraulic system, which powered AICS, wingsweep and flight controls. This BiDi check was important, it allowed either hydraulic system to power the other side, at a slightly reduced pressure. A failed Bidi could leave you without critical components in the event of a hydraulic failure. A BiDi that was engaged with a failed system would overheat on the side with no fluid. So, you had to check that it would 1. work and 2. could be shut off.
After the engines were running, you then went through a test of the AICS, which was called OBC, and the ramps in the inlet would move full deflection and back up to a stowed position for takeoff (they start moving in flight as a function of Mach number, and became relevant above 0.9 IMN). After OBC, then the wings come out to 20 degrees, landing flaps selected, flight controls checked, spoiler operation checked, flaps up, maneuver flaps selected, wings manually selected to aft, observe that they stop at 50 degrees, retract maneuver flaps, sweep to 55 degrees, then sweep to 68 and stow to oversweep for taxi. (On the ship, it was abbreviated to simply: wings to 20 degrees, landing flaps selected, quick spoiler check, then hook up into catapult, mil/AB power selected, flight controls check, and launch.)
The whole normal start/preflight check sequence was long, involving tests of the air inlet control system, wingsweep and flap interlocks and flight controls.
But to start the engines was pretty straightforward: power connected, starter air connected, electric lights test, fire warning system test. Engine start switch to the engine being started (this opened a valve on the air turbine starter and began turning the engine). As the RPM advanced above 18% RPM (minimum, we generally went for the maximum that the starter air source would give us), move the throttle for that engine from cut-off to idle, watch for fuel flow (about 400#/hour flow to start), within a few seconds of fuel flow, the TIT (Turbine Inlet Temperature) should rise. If TIT was rising rapidly (hot start), or if there was no rise (wet start), or the RPM did not advance normally (hung start), then move the throttle back to cutoff and allow the starter to windmill the engine until cool/clear.
The F-110 motor was similar, except that there was a digital gauge for RPM, with an illuminated pixel for fuel-on, so you weren't counting RPM as closely. The F-110 had EGT as a gauge, not TIT, and the limits were different. The digital engine controls on that engine made it more reliable on start than the hydro pneumatic TF-30 engine controls.
Once the left engine was running, you would crank the right, engage the bi-directional hydraulic pump, and stop cranking the right. As the engine wound down, observe that the BiDi picked up the right engine hydraulic system pressure, then cut the BiDi off to make sure that the selector switch for it worked*.
Then start the right engine as the left.
*There were two hydraulic systems, the left engine powered the combined system, which included landing gear, brakes, refueling probe, AICS, wingsweep and flight controls, and the right engine powered the flight hydraulic system, which powered AICS, wingsweep and flight controls. This BiDi check was important, it allowed either hydraulic system to power the other side, at a slightly reduced pressure. A failed Bidi could leave you without critical components in the event of a hydraulic failure. A BiDi that was engaged with a failed system would overheat on the side with no fluid. So, you had to check that it would 1. work and 2. could be shut off.
After the engines were running, you then went through a test of the AICS, which was called OBC, and the ramps in the inlet would move full deflection and back up to a stowed position for takeoff (they start moving in flight as a function of Mach number, and became relevant above 0.9 IMN). After OBC, then the wings come out to 20 degrees, landing flaps selected, flight controls checked, spoiler operation checked, flaps up, maneuver flaps selected, wings manually selected to aft, observe that they stop at 50 degrees, retract maneuver flaps, sweep to 55 degrees, then sweep to 68 and stow to oversweep for taxi. (On the ship, it was abbreviated to simply: wings to 20 degrees, landing flaps selected, quick spoiler check, then hook up into catapult, mil/AB power selected, flight controls check, and launch.)
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One quick start story: I was having trouble getting the left engine started on an F-14A one day at Oceana NAS in Virginia Beach. It wet started three times in a row. Each time, I had fuel flow, but no rise in TIT, so fuel was going in, but combustion wasn't starting. There are limits on the air turbine starter operation, two minutes, I think, can't remember now, so I waited after each failed attempt to let the air turbine starter windmill the engine ( to clear the excess fuel) and then let the airplane sit for the required cooling off period on the starter.
On the fourth or fifth start attempt, with the advice from our maintenance control chief on the radio, I selected "kneel" on the airplane, compressing the nose strut for catapult launch, that tilted the airplane nose down, hoping to get any residual fuel to slosh forward and clear of the igniter plugs in the engine.
It worked.
Sort of.
On that start, as I moved the throttle to idle (which energized the igniters in addition to starting the fuel flow), I heard a "whumpf" inside the airplane and saw the TIT move immediately towards the max for start. I put the throttle back in cutoff. I looked up towards my plane captain to signal her that I was having another start problem, but she was wide-eyed and backing up quickly away from the airplane.
A quick check of the mirrors - I had orange flame licking up the vertical tail from all the puddled fuel in the engine burning...above the flame was heavy black smoke...a bit disconcerting...
But the fire was inside the engine, where it mostly belonged, and I had no fire warning indications that would indicate fire on the outside of the engine, so I continued to let the engine crank with the starter engaged and the fuel off until the smoke and fire cleared.
Once we let the starter cool off, we tried one more time. The engine started normally that time.
So, we went flying on mission.
On the fourth or fifth start attempt, with the advice from our maintenance control chief on the radio, I selected "kneel" on the airplane, compressing the nose strut for catapult launch, that tilted the airplane nose down, hoping to get any residual fuel to slosh forward and clear of the igniter plugs in the engine.
It worked.
Sort of.
On that start, as I moved the throttle to idle (which energized the igniters in addition to starting the fuel flow), I heard a "whumpf" inside the airplane and saw the TIT move immediately towards the max for start. I put the throttle back in cutoff. I looked up towards my plane captain to signal her that I was having another start problem, but she was wide-eyed and backing up quickly away from the airplane.
A quick check of the mirrors - I had orange flame licking up the vertical tail from all the puddled fuel in the engine burning...above the flame was heavy black smoke...a bit disconcerting...
But the fire was inside the engine, where it mostly belonged, and I had no fire warning indications that would indicate fire on the outside of the engine, so I continued to let the engine crank with the starter engaged and the fuel off until the smoke and fire cleared.
Once we let the starter cool off, we tried one more time. The engine started normally that time.
So, we went flying on mission.
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