F-14AM - The Iranian Tomcat - History, Performance, and Discussion

@sudo_su1 All HAWK, Phoenix derivatives should maneuver in combined plane. I believe 20G is the limit for the HAWK - but it is achieved in combined plane.

The Phoenix should also get the combined plane maneuverability.

Even if Gaijin is waiting on a direct statement from a primary source stating that they can maneuver in combined plane - we know that they are mounted in “X” configuration always and they pitch up without a roll command immediately after launch. This is between the two axis’ of the missile control scheme.

@David_Bowie How is that not sufficient for Gaijin? When will we see the AIM-54 corrected to 25G?

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The document you posts says 20g in each plane (so 28 g combined):
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It states 20G and 22 degrees in each plane, not 20G in each plane. It is stating that the fins each individually pitch 22 degrees.

Actually it discusses 20G being a structural limitation.

@DirectSupport

The pitch / yaw commands need to be limited to allow tolerance for roll control, if the autopilot attempts to pitch full towards a target and then needs to roll, it leads to loss of the missile roll control and subsequent breakup occurs.

It states that the autopilot will switch to single plane pitch when pitch and yaw are already limited such as to place the maneuver forces on a single pair of wings rather than equally on both sets. This would likely occur at high speed when AoA is low and roll control is not impeded by airflow interference over the body and fourth control surface.

So the HAWK, which predates the PHOENIX switches between single and combined plane as necessary to maintain highest overload toward targets while simultaneously keeping the missile from departing controlled flight.

@David_Bowie
It quite literally states here that the missile maneuvers in whichever axis the autopilot deems necessary at the time.

To add to that - the structural integrity of the wing…

The absolute peak structural integrity is no more than 25.7G. The wing was not intended for 20G, rather only ~14G in pitch and yaw planes with a vector resultant of 19.8G. What this is discussing is the pitch vector.

The original missile was designed with an X plane maneuvering load limit of ~20G. The single plane maneuverability is usually quoted as 15G, the actual load limit of the design is 12G +/- 2 as stated (14G). 14 squared is 196. 196 + 196 = 392. The square root of 392 is 19.79 G @Flame2512

The combined plane overload is intended to be 20G.
@David_Bowie They should either reduce the Sedjil to single plane of 14-15G or model the combined plane maneuvering limit of 20G. If they use combined plane - they should do so for the Phoenix as well which should be approximately 17G per axis and 24G combined with a similar overshoot of +/-2G that would be ~26.8G. To round that out we can use your source and simply put it at 25G.

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To put simply the changes that were made to make the missile more reliable;
The maximum fin deflection is 22 degrees. The missile sometimes had a tendency to maximum pitch (22 degrees) with 20G overload towards targets and would then need to roll to keep up with target’s defensive maneuver.

Since 22 degrees is already the maximum deflection, roll was not possible while maintaining target intercept and the missile would lose control / breakup.

The solution was to allow 20G maximum pitch but limit fin deflection to 15 degrees in final intercept, this likely led to inferior over-leading characteristics that drained the missile of energy if the target chose to crank sooner… but the missile could actually reach the target. 15 degrees allowed a further 7 degrees for rapid roll response without causing too much pitch-roll-yaw type coupling and oscillations.

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Do you know if the f14 iff works in sim

image

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Thx, was confused whether sim has iff realistically or how it works in air rb

https://community.gaijin.net/p/warthunder/i/62aqRWP8TtYp?comment=N7TcOL1E4o4gWg7vWGPpmovl

@InterFleet Thanks for forwarding the length.

my issue is how can the in game Fakour sits at ~600kg, while the dimensions are smaller than the AIM-54…
Something doesn’t add up

There is likely a lot of empty space inside the AIM-54, including inside the motor.
Also, the density of the propellants might be different (e.g. M112’s propellant might have higher aluminum content).

A cylinder with a length of 3.96m and a diameter of 356mm has a volume of 394 liters (And obviously most parts that are used in a missile, including the body, warhead, and propellant, have a density quite a bit higher than 1).

Just look at this chart. The M112 motor itself, which has a diameter of 356mm and a length of just 2.678m (with “tail can and 3 fins”), already weighs almost as much as a full blown AIM-54A.

I think u replied to wrong person

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Yeah, my bad.
Wanted to reply to the topic, instead I replied to your post.

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Fakour-90 incorrect guidance delay:

https://community.gaijin.net/issues/p/warthunder/i/wkcE1qjLUOeS

If so, it should be returned. I will write a report.

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The missile can reach 20G in single plane per the document, that is the commanded limit due to structural concerns.
Though I think it highlights how important it is Gaijin fix the Phoenix so they can begin balancing the Tomcat.

I was only highlighting how most missiles mounted in “X” configuration actually can, and do, maneuver in combined plane as needed.

This will be a separate suggestion, currently we only implement single plane maneuverability, so there will be a bug report to revert this and a suggestion to implement dual plane maneuverability.

It will only affect the I-Hawk while F90 keeps its 20G, correct?

Literally says originally the wings were 14G’s single plane, and then extended to 20G’s single plane creating “loads that were significantly than those originally designed for”

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That does make some sense.

From what I understand from this, originally I-Hawk’s wings were designed for the same G limit as basic Hawk, but then during development, they changed the “threat g level” from 3 g to 6 g and consequently, changed the missile guidance and increased the missile G and AoA limits to meet the new requirements:

The problem however, is with this part:

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From what I understand from this, the autopilot uses single plane maneuvering as long as there is no need to use max pull, and switches to dual plane when it needs max pull.

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