The Real Questions...

[Czechnology]

1) Anyone have a full cold start checklist yet?

2) Anyone know the abilities of our nav system? I've been reading USAF Phantoms and to my understanding we get INS, but does that just give a Lat-long readout, or what?

3) Anyone have info on how our IFF works?

[Omega417]

10 hours ago, Czechnology said:

1) Anyone have a full cold start checklist yet?

2) Anyone know the abilities of our nav system? I've been reading USAF Phantoms and to my understanding we get INS, but does that just give a Lat-long readout, or what?

3) Anyone have info on how our IFF works?

1) Ive just copied down what the manual has listed but Im not sure how accurate it is.

2) based on the cockpit drawings from the manual I think the pilot just gets a readout and the backseater gets the controls, looks almost like an A4. But, I am not versed so I will probably get yelled at for being wrong. nullnull

[Aussie_Mantis]

11 hours ago, Czechnology said:

1) Anyone have a full cold start checklist yet?

2) Anyone know the abilities of our nav system? I've been reading USAF Phantoms and to my understanding we get INS, but does that just give a Lat-long readout, or what?

3) Anyone have info on how our IFF works?

Cold start I have no idea, I know how to do it with the Cart attached, though, which is:

1. Check master caution & reset
2. Check O2
3. throttles to OFF (not idle)
4. air on #2/cartridge fwoosh, it's done externally not internally IIRC but I could be wrong, never was sure about the cartridges. Know that air was defo external.
5. Wait for rotation on #2
6.  at 10% hold ignition and advance throttle to 50% and then back to idle, release ignition and call lightoff
7. check oil and hydraulics
8. air off at 45% if cart start
9. cycle right generator
10. test spoilers i.e. ailerons
11. air/cartridge #1 and repeat steps 4-8 for engine #1
12. external doors check clear, disconnect all power and air connections to outside
13. clear and check airbrake up and down
14. check flaps, cycle down and then back up
15. check all other controls, pitch roll yaw etc etc
16. check all augmented stabilities in order yaw --> aileron --> pitch
17. double check tires, iFF, Altimeter
18. activate SPC and taxi

Before takeoff ensure you check wing tank transfer is on (not external tanks) and internal tank 5 and 6 lockout (these tanks along with the wing tanks're closest to the transsonic centre of maneuvering and help keep the center of gravity nice and close to your aerodynamic centre, so only use them when you REALLY have to), engage all stability augmentors,reconfirm controls and trim, close cockpits, check pitot heat is good, double check IFF and circuit breakers if you're the RIO, flaps down to takeoff (i.e. slats + takeoff flaps, setting #3(?)) and then engines to burner and go!

Edited January 4, 2023 by Aussie_Mantis

[Aussie_Mantis]

12 hours ago, Czechnology said:

1) Anyone have a full cold start checklist yet?

2) Anyone know the abilities of our nav system? I've been reading USAF Phantoms and to my understanding we get INS, but does that just give a Lat-long readout, or what?

3) Anyone have info on how our IFF works?

for the other questions which I didn't answer- sorry-

The USAF Phantoms have LORAN and other such INS or beacon-based systems that just give you a readout for lat-long or your heading and distance from a beacon, I think. It's not that great but it'll do.

As for the IFF, most early phantoms did not have built-in IFF. the USAF trialled the APX-80 Combat Tree IFF system on the F-4D (the D had a slightly superior radar on account of the dish being bigger, along with better scan presets) and that's a similar system to what would come later. Oddly enough I think the benefit of IFF wasn't really the fact that you got IFF but also that you could acquire MIGs from longer ranges on the F-4D, particularly with its very terrain clutter-sensitive radar set. It should give you little markers on your screen for friendlies and enemies.

F-4Es however don't use APX-80 from what I know and you need to visually identify the enemy to actually kill them, hence TISEO and associated bells & whistles. The radar display is extremely basic and looks like something out of War Thunder, with a central acquisition "puck" (or whatever that little thing with the two bars is called) that goes around your screen when you select a target. This is more the WSO's thing, and the pilot only has Automated Acquisition (boresight) or on later variants CAA (Computer Assissted Acquisition), which is boresight with a few filters to help discriminate targets against terrain/noise and thus doesn't discriminate, she just locks.

As far as I know it (CAA and APX-80) are USAF only, not USN. I don't know if USN radars had IFF or not.

Edited January 4, 2023 by Aussie_Mantis

[SgtPappy]

5 hours ago, Aussie_Mantis said:

for the other questions which I didn't answer- sorry-

The USAF Phantoms have LORAN and other such INS or beacon-based systems that just give you a readout for lat-long or your heading and distance from a beacon, I think. It's not that great but it'll do.

As for the IFF, most early phantoms did not have built-in IFF. the USAF trialled the APX-80 Combat Tree IFF system on the F-4D (the D had a slightly superior radar on account of the dish being bigger, along with better scan presets) and that's a similar system to what would come later. Oddly enough I think the benefit of IFF wasn't really the fact that you got IFF but also that you could acquire MIGs from longer ranges on the F-4D, particularly with its very terrain clutter-sensitive radar set. It should give you little markers on your screen for friendlies and enemies.

F-4Es however don't use APX-80 from what I know and you need to visually identify the enemy to actually kill them, hence TISEO and associated bells & whistles. The radar display is extremely basic and looks like something out of War Thunder, with a central acquisition "puck" (or whatever that little thing with the two bars is called) that goes around your screen when you select a target. This is more the WSO's thing, and the pilot only has Automated Acquisition (boresight) or on later variants CAA (Computer Assissted Acquisition), which is boresight with a few filters to help discriminate targets against terrain/noise and thus doesn't discriminate, she just locks.

As far as I know it (CAA and APX-80) are USAF only, not USN. I don't know if USN radars had IFF or not.

 

Some but not all the Rivet Haste F-4E's did indeed have Combat Tree installed when they were flown in combat during the last months of the US involvement in Vietnam.

The F-4 production chart also states that the APX-80 was built into a bunch of F-4E blocks but likely deleted for most export planes.

[Goldeagle365]

8 hours ago, Aussie_Mantis said:

The USAF Phantoms have LORAN and other such INS or beacon-based systems that just give you a readout for lat-long or your heading and distance from a beacon, I think. It's not that great but it'll do.

F-4Es however don't use APX-80 from what I know and you need to visually identify the enemy to actually kill them, hence TISEO and associated bells & whistles. The radar display is extremely basic and looks like something out of War Thunder, with a central acquisition "puck" (or whatever that little thing with the two bars is called) that goes around your screen when you select a target. This is more the WSO's thing, and the pilot only has Automated Acquisition (boresight) or on later variants CAA (Computer Assissted Acquisition), which is boresight with a few filters to help discriminate targets against terrain/noise and thus doesn't discriminate, she just locks.

As far as I know it (CAA and APX-80) are USAF only, not USN. I don't know if USN radars had IFF or not.

 

To add to this, the navigation is old school by modern standards but pretty typical for the day. TACAN, ADF, VOR/ILS, and an inertial navigation system (INS) (controlled via the AN/ASN-46 panel in the WSO's pit). The INS gives aircraft lat long, bearing and distance to 2 stored targets, aircraft ground speed, magnetic ground track and drift angle. This all integrates into the HSI and ADI (as applicable). 

 

As for IFF, my sources show provisions and mentions of the APX-80 or APX-81 set as being installed, but as to how the system works/is integrated or if they were retained, I'm not sure. 

[Aussie_Mantis]

4 hours ago, SgtPappy said:

Some but not all the Rivet Haste F-4E's did indeed have Combat Tree installed when they were flown in combat during the last months of the US involvement in Vietnam.

The F-4 production chart also states that the APX-80 was built into a bunch of F-4E blocks but likely deleted for most export planes.

Ah, excellent. Thanks!

Pappy, I know you flew the old RAF F-4Ms back in the day- did they have any similar systems on the old Marconi License-builds?

Also, do you have discord? Would love to interview you at some point.

1 hour ago, Goldeagle365 said:

To add to this, the navigation is old school by modern standards but pretty typical for the day. TACAN, ADF, VOR/ILS, and an inertial navigation system (INS) (controlled via the AN/ASN-46 panel in the WSO's pit). The INS gives aircraft lat long, bearing and distance to 2 stored targets, aircraft ground speed, magnetic ground track and drift angle. This all integrates into the HSI and ADI (as applicable). 

 

As for IFF, my sources show provisions and mentions of the APX-80 or APX-81 set as being installed, but as to how the system works/is integrated or if they were retained, I'm not sure. 

RE IFF to both you and Pappy, I rechecked my sources- T.O. 1F-4E-1 '86 says that it was indeed installed at some point. Not sure if it was standard prior to 1975, but it's there.

 

Does anyone know anything about the later F-4E's radar warning reciever? Iheard they used AN/ALR-69 past 1978 and DMAS, giving it a full digital RWR threat receiver suite like the A-10, but I'm not sure.

[JNelson]

2 hours ago, Goldeagle365 said:

To add to this, the navigation is old school by modern standards but pretty typical for the day. TACAN, ADF, VOR/ILS, and an inertial navigation system (INS) (controlled via the AN/ASN-46 panel in the WSO's pit). The INS gives aircraft lat long, bearing and distance to 2 stored targets, aircraft ground speed, magnetic ground track and drift angle. This all integrates into the HSI and ADI (as applicable). 

 

As for IFF, my sources show provisions and mentions of the APX-80 or APX-81 set as being installed, but as to how the system works/is integrated or if they were retained, I'm not sure. 

iirc, it was fairly common. You can look up pictures of the AN/APQ-120 dish most of them have iff antennas installed.

[SgtPappy]

32 minutes ago, Aussie_Mantis said:

Ah, excellent. Thanks!

Pappy, I know you flew the old RAF F-4Ms back in the day- did they have any similar systems on the old Marconi License-builds?

Also, do you have discord? Would love to interview you at some point.

RE IFF to both you and Pappy, I rechecked my sources- T.O. 1F-4E-1 '86 says that it was indeed installed at some point. Not sure if it was standard prior to 1975, but it's there.

 

Does anyone know anything about the later F-4E's radar warning reciever? Iheard they used AN/ALR-69 past 1978 and DMAS, giving it a full digital RWR threat receiver suite like the A-10, but I'm not sure.

I'm humbled but you might be mistaking me for GJS! They flew the Phantom in the UK.

The APX-80/81 was standard starting with Block 48, per JNelson's comment.

[Aussie_Mantis]

38 minutes ago, SgtPappy said:

I'm humbled but you might be mistaking me for GJS! They flew the Phantom in the UK.

The APX-80/81 was standard starting with Block 48, per JNelson's comment.

Feck.

 

Also RE the IFF, does anyone have any pics?

[Aussie_Mantis]

speaking of @G.J.S- heya! Do you happen to remember any cold start procedures for the F-4M? I don't know if it's similar or different to the F-4E procedure I mentioned earlier but it might help either way!

 

Also, did the RAF/FAA Phantoms get IFF?

Edited January 5, 2023 by Aussie_Mantis

[SgtPappy]

1 hour ago, Aussie_Mantis said:

Feck.

 

Also RE the IFF, does anyone have any pics?

The only pictures I've seen of the IFF on the F-4 are the antennas shown on the APQ parabolic dish. I'm sure there's a bunch of hardware hidden elsewhere in the jet.

APQ-120 on the F-4E with 4 IFF antennas:

 

APQ-109 on F-4D without antennas for comparison:

 

 

APQ-109 with 8 antennas:

[Aussie_Mantis]

2 hours ago, SgtPappy said:

APQ-109 with 8 antennas:

"Hey, so how many antennas we gotta put on that thing"

"ALL OF THEM, CARMICHAEL! PUT ALL OF THEM ON!"

[KlarSnow]

The IFF for the Phantom is the AN/APX-76, It was installed as early as 1966-7 on F-4C's and D's. It was standard on F-4E's.

The AN/APX-80/81 get a bit confusing because they are either a combined AN/APX-76 and Combat Tree (AN/APX-81), or just Combat Tree on its own separate from the AN/APX-76 (AN/APX-80)

Technical Order 1-F-4-753, Installation of air-to-air IFF system.

Production Effectivity: All F-4E, Retrofit Effectivity: the stated F-4C's and F-4D's. At least as of 1970. Here is the TO effectivity from a 1970 F-4C-1 (which also applies to F-4D/E)

And here is the line from the CNI section that directly labels it as the AN/APX-76, This btw is the exact same system as was installed and is currently implemented on the F-14 in DCS.

[Goldeagle365]

SgtPappy, many thanks for the info! I've always wondered what the t shaped antenna where on the APQ series dish! 

KlarSnow, thats some diggin you've done! 

JNelson, thats a great point!. 

 

[Czechnology]

I think a follow up question is in order for the IFF system. We did a lot of talking of what the system did, whether it was on the bird, and all the antennas, but the question of how the thing works wasn't really answered!

Do we manually interrogate like on the Mig 21 or F-14, or is the radar continuously interrogating? What does a friendly or hostile marker look like? Do we have to lock a target to interrogate? Does it even work on locked targets? Is it displayed on the radar screen, or somewhere else?

Edited January 15, 2023 by Czechnology

[Czechnology]

Also a follow up question that's more history related, why did the F-4 originally come without an IFF? Wouldn't IFF be crucial to perform BVR intercepts without risk of friendly fire, like the bird was designed for? Mig 21s at the time were coming with them, as shown in our use of the Combat Tree system, so what gives? Just one of those handful of times the Soviets were ahead of us, or some other reason?

[KlarSnow]

The jets had IFF from the beginning, a transponder to respond to interrogations. The Combat Tree system was an interrogator that interrogated Soviet Transponders, not Mig-21s having interrogators (not saying they didn't have them). All Combat Tree shows is that vietnamese Migs had IFF Transponders, not necessarily interrogators. These are not the same things.

The phantom wasn't designed in a vacuum. It was designed to intercept things with the support of other entities that could help with the ID, and was intended to be vectored against incoming bomber streams with very clear ROE solved from the moment they began the intercept.

In hindsight of course that wasn't how it worked out, but there was nothing really "behind" about it.

Its just how the evolution of air combat and doctrine works. You build your systems based on how you think will best win the fight you assume you are going to have. When that's not the fight you end up fighting, then you adapt.

Again the Phantom (F-4C) was in service with the USAF and USN for like 3-4 years before it got the AN/APX-76. It had them for the next 40 plus.......... That's a very short time in its entire lifespan without them. And it only manifested itself in a poor way due to the conflict they were in in 1965-1967.

The first Phantom v MIG engagement of Vietnam was a USN F-4B engagement, They targeted and locked the incoming Migs and fired a single Sparrow each head on at the VID (around 3-4 miles). Two shots, two kills. This was 2 years after the Phantom had entered service. You wouldn't be wrong for thinking after that engagement that maybe not having an interrogator wasn't a big deal, and using sparrows as your primary weapon was the right choice.

[Elf1606688794]

On 1/4/2023 at 7:47 AM, Aussie_Mantis said:

F-4Es however don't use APX-80 from what I know and you need to visually identify the enemy to actually kill them, hence TISEO and associated bells & whistles.

F-4E's had some sort of IFF system, at least the ones at Seymour Johnson did. During an ORI (Operational Readiness Inspection) while I was there an inspector would stand close to the EOR operations (End of Runway) for takeoffs looking through a box thingie. What he was looking for was an IFF signal that aircrews were supposed to have turned on before taxiing.

I have no idea how that black box the inspector looked through worked I just know what I was told. 

[RebelHusky]

Anybody here got info on that persistence and wear + tear mechanics that HB mentioned in the newsletter?

It sounds like something very interesting but no info available so far

[RevampedGrunt]

1 hour ago, RebelHusky said:

Anybody here got info on that persistence and wear + tear mechanics that HB mentioned in the newsletter?

It sounds like something very interesting but no info available so far

What would this entail? Damage overtime via a mission or something?

[Aussie_Mantis]

On 1/15/2023 at 9:49 PM, Czechnology said:

Also a follow up question that's more history related, why did the F-4 originally come without an IFF? Wouldn't IFF be crucial to perform BVR intercepts without risk of friendly fire, like the bird was designed for? Mig 21s at the time were coming with them, as shown in our use of the Combat Tree system, so what gives? Just one of those handful of times the Soviets were ahead of us, or some other reason?

It automatically interrogated friendly IFFs, but Combat Tree was the first to interrogate enemy IFFs so you could get a definite "Yep, that's definitely an enemy contact" signal bounced back. It really helps when you know without any doubt that that contact at 100nmi is definitely an enemy MiG-21 and not, say, an F-4 with a busted IFF transponder.

On 1/15/2023 at 9:49 PM, Czechnology said:

Also a follow up question that's more history related, why did the F-4 originally come without an IFF? Wouldn't IFF be crucial to perform BVR intercepts without risk of friendly fire, like the bird was designed for? Mig 21s at the time were coming with them, as shown in our use of the Combat Tree system, so what gives? Just one of those handful of times the Soviets were ahead of us, or some other reason?

They did technically have IFF, just not one interrogating enemy RADAR contacts, which is why they wanted Combat Tree to distinguish Unknowns and definite enemies. Really helps.

[RebelHusky]

22 hours ago, RevampedGrunt said:

What would this entail? Damage overtime via a mission or something?

Unsure really. Would be a nice mechanic to have wear on flight systems such as engines that slowly start to perform worse during singleplayer campaigns for example.

I saw HB mention it in their 2023 start of the year post in the Phantom section and as I could understand it didn't relate to wear and tear weathering on the liveries

[Omega417]

How long is it going to take us to align our INS?

[unlikely_spider]

6 minutes ago, Omega417 said:

How long is it going to take us to align our INS?

Two weeks