HUD pitch ladder

[AH_Solid_Snake]

From memory the FPM we have is a little more accurate than the real world one too, so even using it in the recovery context is a DCSism, multiple sources including @Victory205 have stated that turning the HUD off entirely was common practice.

 

I’m not sure if the FPM is finalised or if that’s going to be subject to a “downgrade” during early access.

[Ben Sones]

2 hours ago, Naquaii said:

 

I think we're talking about different things here. If you place horizon line on the HUD on the wings the aircraft will be in level flight. That's exactly it's purpose and also how an ADI works.

 

Saying that it's referencing the real world like a modern HUD isn't though. If it did the horizon line on the HUD would always exactly mark the real horizon in the outside world, that the F-14 HUD can't do. You can trim it to be at the horizon in the real world but a change of altitude or even a roll will change this and make it not so. This fact is what makes it not reference the real world in the HUD sense. The ADI function will always work and show aircraft aspect though, as long as you only check the pitch ladder against the other HUD symbology, not the outside world. In a modern HUD you would always be able to use all these symbols against the real world outside as well and the lack of this in the F-14 is what disqualifies it as a primary flight instrument.

 

This coupled with the lack of granularity/resolution and speed of update is what made the real pilots turn it off and not use it as many preferred to just use the VDI instead as it was less confusing and also how many were used to if they transferred from older aircraft.

 

The lack of an in detail description of the HUD in the manual is on my todo list and will be added.

 

 

 

Right, I understand that it doesn't mark the real world horizon, and instead gives you attitude information relative to the HUD reticle. I explained that in my first post (that was actually the whole point of my first post, because how the HUD's ADI works is not at all intuitive, and also not explained anywhere), and it seemed like you were saying that was wrong, but perhaps I misunderstood? Really, all I was trying to do was figure out what the data on the HUD represents, and through experimentation I came to the conclusion that:

 

1. The reticle corresponds with the nose of the aircraft. 

 

2. The ADL cross corresponds with the longitudinal line of the wings.

 

3. The ADI ladder is calibrated to show pitch relative to the position of the reticle. 

 

Are any of those observations incorrect? I also understand that the HUD's ADI wasn't intended to be a primary flight instrument on the real F-14. But, that said, doesn't it technically work in exactly the same way as the SAI gauge, which is a primary flight instrument? The SAI is also just a gyro-based mechanism that doesn't reference anything outside the aircraft, and that can be trimmed to display incorrect information. 

 

[Naquaii]

10 minutes ago, Ben Sones said:

 

 

Right, I understand that it doesn't mark the real world horizon, and instead gives you attitude information relative to the HUD reticle. I explained that in my first post (that was actually the whole point of my first post, because how the HUD's ADI works is not at all intuitive, and also not explained anywhere), and it seemed like you were saying that was wrong, but perhaps I misunderstood? Really, all I was trying to do was figure out what the data on the HUD represents, and through experimentation I came to the conclusion that:

 

1. The reticle corresponds with the nose of the aircraft. 

 

2. The ADL cross corresponds with the longitudinal line of the wings.

 

3. The ADI ladder is calibrated to show pitch relative to the position of the reticle. 

 

Are any of those observations incorrect? I also understand that the HUD's ADI wasn't intended to be a primary flight instrument on the real F-14. But, that said, doesn't it technically work in exactly the same way as the SAI gauge, which is a primary flight instrument? The SAI is also just a gyro-based mechanism that doesn't reference anything outside the aircraft, and that can be trimmed to display incorrect information. 

 

 

The thing I got hung up on was your wording that it referenced the real world, and in a HUD that means that the symbology matches up with the outside world, which the pitch ladder on the HUD doesn't in the F-14.

 

The thing is that if you look at the pitch ladder on the HUD like it being a digital ADI displayed on the HUD it's completely intuitive. The reason for it not being so is that many people expect it to behave like a modern HUD when in this case it's just a display device like the VDI.

 

The aircraft wings on the HUD does represent the aircraft nose when used in conjuction with the pitch lines, that's true like on an ADI guage and it's designed to show pitch relative that. That's not a calibration, it's just showing attitude from the INS. The ADL is not designed to be anything other than an indication of weapon boresight, anything else is co-incidental.

So yeah, 2 out of your 3 observations are correct as the pitch ladder wouldn't be of much use else and are kinda inferred by the pitch ladder and aircraft wings indicator being designed as an ADI display.

 

And yes, the pitch ladder on the HUD is designed to work like an ADI and thus also a SAI but like I've said multiple times now the resolution and update rate weren't good enough for it to be considered a primary flight instrument.

[Spartan111sqn]

it is also clear for me that a standard break turn on a Tomcat is not easy if you want to keep the altitude with precision, honestly mates how do you manage to do it properlly?, since there is no FPM you are always going up or down on a turn.

[Skysurfer]

23 minutes ago, Spartan111sqn said:

it is also clear for me that a standard break turn on a Tomcat is not easy if you want to keep the altitude with precision, honestly mates how do you manage to do it properlly?, since there is no FPM you are always going up or down on a turn.

 

VDI or simply remember the visual picture you see (nose cutting across the horizon) for a level turn during the break. 

[Ben Sones]

17 minutes ago, Spartan111sqn said:

it is also clear for me that a standard break turn on a Tomcat is not easy if you want to keep the altitude with precision, honestly mates how do you manage to do it properlly?, since there is no FPM you are always going up or down on a turn.

 

There is an FPM when the HUD is in landing mode, actually. I wish it were there in all modes (though it seems to get a lot less accurate at high speeds--I've tried putting the HUD in landing mode during regular flight, just to mess around with it, and the FPM seems to wander off in random directions at speeds over 400-500 knots). The FPM is one of those instances where not understanding how the ADI works will mess you up, because the FPM is calibrated to the world, and not to the ADI. So if it's over the HUD's horizon line, you are actually in a ~4-degree descent. You want to put it over the real horizon to maintain level flight. 

 

And yeah, managing the Tomcat through a circuit landing is not easy. I've been practicing, and I can land consistently without crashing, but they still aren't particularly good landings. There's already a lot to manage in that sort of landing, in any aircraft--maintaining altitude and speed, keeping the aircraft trimmed while also doing things like reducing speed and deploying gear and flaps and speedbrakes, all of which throw off your trim. On top of all that, the Tomcat adds cycling wing sweep all the way back and then all the way forward again (which hugely throws off your trim), and the DLC system, which will push you right into the ground (or ocean) if you don't use it correctly.

 

I had the DLC controls mapped to a hat switch, like Chuck's guide suggests, but after struggling with landings I ended up moving it to an axis. I have a CH Fighterstick and Throttle, and the stick has a dial on the base, meant to be used as a Z-axis for people that don't have a standalone throttle. Since I'm using my actual throttle as a Z-axis, I assigned the stick's dial to DLC, and that helped a lot. Having a fine degree of control over the angle of the spoilers, rather than just cycling them back and forth between full up and full down, really makes a difference. (The real F-14 has a dial for DLC control, too.)

 

 

47 minutes ago, Naquaii said:

The ADL is not designed to be anything other than an indication of weapon boresight, anything else is co-incidental.

 

Right, I understand that the ADL cross is not intended to show you the longitudinal line of the wings. I'm just saying that in practice it does seem to show you that, just by virtue of the fact that your weapons are mounted close to the wings and face the same direction. 

 

 

[Naquaii]

3 minutes ago, Ben Sones said:

I had the DLC controls mapped to a hat switch, like Chuck's guide suggests, but after struggling with landings I ended up moving it to an axis. I have a CH Fighterstick and Throttle, and the stick has a dial on the base, meant to be used as a Z-axis for people that don't have a standalone throttle. Since I'm using my actual throttle as a Z-axis, I assigned the stick's dial to DLC, and that helped a lot. Having a fine degree of control over the angle of the spoilers, rather than just cycling them back and forth between full up and full down, really makes a difference. (The real F-14 has a dial for DLC control, too.)

 

Yeah, the real world DLC thumbwheel was stepless and springloaded to center. IRL they were taught not to use it like that though as it was intended for momentary corrections of position in the glideslope. So normally they'd just bang it fully in either direction a couple of times to correct, not hold it partially in either direction continuously.

 

That said, using it gradually would absolutely work, either momentarily or continuously. But not how it was done IRL.

 

6 minutes ago, Ben Sones said:

Right, I understand that the ADL cross is not intended to show you the longitudinal line of the wings. I'm just saying that in practice it does seem to show you that, just by virtue of the fact that your weapons are mounted close to the wings and face the same direction. 

 

Yes, and that's all well and good. All I'm saying is that it wasn't intended do to this IRL unlike your conclusion and it might not be exactly true. But if it works for you, why not use it like that.

[captain_dalan]

1 hour ago, Spartan111sqn said:

it is also clear for me that a standard break turn on a Tomcat is not easy if you want to keep the altitude with precision, honestly mates how do you manage to do it properlly?, since there is no FPM you are always going up or down on a turn.

Add some rudder to keep the turn coordinated and control the descent rate by changing bank angle. Also...... VDI. But i mostly do it by eye.

[AH_Solid_Snake]

I think as Naquaii has pointed out a few times, the F-14 is a 3rd generation fighter with 4th gen performance.

 

If you think back to crews transitioning from jets like the F4, (did any transition straight from F8s?) then the HUD is a step up, there are many more cues for visual range weapon release, which was the entire requirement.

 

The additional expectations of things like FPM, pitch ladders etc come from later 4th gen fighters with full on 4th gen avionics, so you will be fighting a huge amount of cognitive dissonance if you persist in thinking of the F-14A / A+ that we have in that regard.

 

The HUD is not a primary flight instrument, and yet, you'll find all the instruments you need are there, they just arent the same as later jets. They are even organised pretty well considering that the official field of ergonomics was sort of made up by a designer of the F-18, that cluster of stuff on your left shows you height, vertical speed, speed.... that thing in front of you shows your pitch ladder and optionally the ILS indications and does so in a much smoother way than the old school HUD.

 

For the break turn, even in case 1 visual conditions to fly the approach right on the numbers you are essentially on an instrument approach until you transition to visual at the end of the final turn, up to that point as many have pointed out - if you want that perfectly level turn at bang on 800 feet refer to your instruments and dont worry too much about whats going on out the window. Thats not to say with a bit of skill you can get used to watching the horizon and maintain a level turn visually, but it was perfectly natural from crews transitioning to the jet in the early 70s in a way thats pretty much anathema to sim pilots in the 2020s, theres just so much expectation that whats very much a dirty analog process subject to all kinds of real world interactions to be a binary, digital, works or not process.

[Spartan111sqn]

7 hours ago, captain_dalan said:

Add some rudder to keep the turn coordinated and control the descent rate by changing bank angle. Also...... VDI. But i mostly do it by eye.

Thanks, rudder in the same direction?, during rolling or all the turn?

And finally the F14D had a HUD even more complete than hornet, in fact similar to hornet one. Also with digital FCS.

 

I would love to have it in DCS.

[TLTeo]

12 hours ago, Naquaii said:

If you place horizon line on the HUD on the wings the aircraft will be in level flight. That's exactly it's purpose and also how an ADI works.

This doesn't account for the aircraft's AoA though, right? E.g. when you're in the grove on speed. with no descent rate, the VDI and HUD show the aircraft being a few degrees nose up.

[Naquaii]

9 minutes ago, TLTeo said:

This doesn't account for the aircraft's AoA though, right? E.g. when you're in the grove on speed. with no descent rate, the VDI and HUD show the aircraft being a few degrees nose up.

 

Yeah, level flight as in the nose pointing straight ahead. Not as in not descending.

 

46 minutes ago, Spartan111sqn said:

Thanks, rudder in the same direction?, during rolling or all the turn?

And finally the F14D had a HUD even more complete than hornet, in fact similar to hornet one. Also with digital FCS.

 

I would love to have it in DCS.

 

In fact the last upgrade of the F-14B had an even better HUD, the Sparrowhawk HUD.

[Dezmond]

9 hours ago, Spartan111sqn said:

it is also clear for me that a standard break turn on a Tomcat is not easy if you want to keep the altitude with precision, honestly mates how do you manage to do it properlly?, since there is no FPM you are always going up or down on a turn.

Bearing in mind that I suck... I find it substantially easier to maintain the correct height while pulling the recommended amount of G. You don’t want to be tentative. The bird seems to track far better when pulling fairly hard.

[draconus]

23 hours ago, Ben Sones said:

There's already a lot to manage in that sort of landing, in any aircraft--maintaining altitude and speed, keeping the aircraft trimmed while also doing things like reducing speed and deploying gear and flaps and speedbrakes, all of which throw off your trim. On top of all that, the Tomcat adds cycling wing sweep all the way back and then all the way forward again (which hugely throws off your trim), and the DLC system, which will push you right into the ground (or ocean) if you don't use it correctly.

You've just named all the devices and procedures that suppose to help you land the Tomcat safely and consistently - not make it harder. If you trim to level flight at 800ft, 350KIAS, hook down, wings 68deg before the break you'll end up almost trimmed when all dirty up and on-speed.

[Spartan111sqn]

On 7/12/2021 at 11:03 PM, Spartan111sqn said:

Thanks, rudder in the same direction?, during rolling or all the turn?

 

 

Could you please give a bit of light here please?

[draconus]

11 minutes ago, Spartan111sqn said:

Could you please give a bit of light here please?

Usually start with gentle rudder into the turn then add lateral stick to start rolling until desired bank is achived then stick is centered laterally (pitch to stay level and/or get desired G) and rudder is held as desired depending on the turn and slip indicator (keep the ball centered).

[Spartan111sqn]

25 minutes ago, draconus said:

Usually start with gentle rudder into the turn then add lateral stick to start rolling until desired bank is achived then stick is centered laterally (pitch to stay level and/or get desired G) and rudder is held as desired depending on the turn and slip indicator (keep the ball centered).

the down ball, right?,

while applying rudder after roll angle is established, due to rudder the aircraft is still rolling a bit?

[draconus]

23 minutes ago, Spartan111sqn said:

while applying rudder after roll angle is established, due to rudder the aircraft is still rolling a bit?

No, you should not roll.

[Spurts]

On 7/12/2021 at 10:19 AM, AH_Solid_Snake said:

I think as Naquaii has pointed out a few times, the F-14 is a 3rd generation fighter with 4th gen performance.

 

I think of the F-14A as a 4th gen airframe with advanced 3rd gen guts.  The B got 4th Gen engines.  The D got 4th Gen electronics.  Overall HMI was still 3rd Gen across the board.  I love flying this bird.  

[TLTeo]

4th gen is very poorly defined anyway, it covers a huge span of time in which the airframes remain the same but more stuff was added on mainly through software. If the Tomcat is a 3rd gen fighter with 4th gen performance, so are an F-15A or F-16A for instance.

[AH_Solid_Snake]

7 minutes ago, TLTeo said:

4th gen is very poorly defined anyway, it covers a huge span of time in which the airframes remain the same but more stuff was added on mainly through software. If the Tomcat is a 3rd gen fighter with 4th gen performance, so are an F-15A or F-16A for instance.

 

Agree and disagree. 4th gen is very much software driven and has more to do with little black boxes than it does the airframe over the longer term. So in that way I would say the F-14 remains a 3rd generation fighter for much of its life since the TF-30 hung around instead of being upgraded, as did the AWG-9, again without much in the way of upgrades.

 

The F-15A and F-16A for sure are very close to the F-14A but those fleets received far more substancial upgrades internally while for a good long time until the very late 80s the only thing keeping the F-14 in-pace with the rest of the teen series was the simple fact it had unique capabilities at the beginning, the Navy had a very hard time finding money to get the B and later D models and never did get as many as they wanted. 

 

A lot of this is just down to happenstance and timeframes. The Navy had a few mis-starts to replace the F4 and when they were talking about F-14 they not only really really wanted that fighter specifically, they were desperate for a replacement for the F4 which had been in service for far too long at that point. Thus they were unwilling to play the Air Force game and wait for avionics and engines to catch up with what Grumman and MacAir were talking about with their next generation airframes. There was also a political aspect of having been strong armed to accept a USAF fighter and "navalize" it by people who didn't understand what the term meant resulting in the F-111B fiasco they knew if they held off from the F-14 it might happen again and they would go without a new fighter even longer until they proved you can't just "navalize" the F-15 without rebuilding it.

 

The original plan for the B and C model Tomcats was to very quickly get good engines and avionics in there, but the F-14 is a victim of budgets and its own success. As the A+ showed the F-14 had huge amounts of untapped potential, but theres a cost associated with it, and even with the TF-30 it was very capable, so why pay it in a period of budget cuts.

 

The USAF played the opposite game and used a brand new radar / HUD / HOTAS concept and also threw in the P&W F100 which had its own set of teething problems, and they still got a fighter after all that risk that was more or less equal to the Tomcat. It was only as the F100 matured into a reliable engine and the APG-63 got software upgrades that the AWG-9 was incapable of that it caught up and arguably surpassed it on some metrics.

[captain_dalan]

On 7/12/2021 at 11:03 PM, Spartan111sqn said:

Thanks, rudder in the same direction?, during rolling or all the turn?

 

Sorry for the late reply, didn't have a chance to log in this week, but @draconus pretty much answered it. Slight rudder in the direction you need to roll, then stick in that direction, then pull and add rudder as needed to keep the ball centered. If performed really well, no rudder will be needed actually, but i seldom do it that precisely.

[captain_dalan]

On 7/14/2021 at 4:16 PM, AH_Solid_Snake said:

 

Agree and disagree. 4th gen is very much software driven and has more to do with little black boxes than it does the airframe over the longer term. So in that way I would say the F-14 remains a 3rd generation fighter for much of its life since the TF-30 hung around instead of being upgraded, as did the AWG-9, again without much in the way of upgrades.

 

 

This largely depends on what in one's opinion defines the fighter generations and is largely a matter of personal choice then a given fact. Similar to what some people perceive was the role of the F-14 actually. Was it maritime air superiority or was it fleet air defense? People who looked for the former would tell you the first answer and people who looked for the latter will tell you the second one. And what do the DoD requirements and fleet manuals say? They actually say both. So IMO, a more accurate classification would be that if we really must classify the F-14 in a generation, but don't wanna spend the next couple of decades what a generation is, then the plane was a 4th generation platform with 3rd generation avionics. Even that wouldn't be an exact answer as in some ways it was before even the 4th gen fighters, I.E. sensor fusion.

[RustBelt]

On 7/12/2021 at 8:29 AM, Spartan111sqn said:

it is also clear for me that a standard break turn on a Tomcat is not easy if you want to keep the altitude with precision, honestly mates how do you manage to do it properlly?, since there is no FPM you are always going up or down on a turn.

Look outside, it's a Visual Maneuver.

[Spartan111sqn]

3 hours ago, RustBelt said:

Look outside, it's a Visual Maneuver.

yes, but it is very easy to go up or down, no exact level flight