If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
Vietnam era F-4s Q
|
#2
|
|||
|
|||
Ed Rasimus wrote:
(Zajcevi) wrote: Hello I would like to ask few questions about Vietnam era F-4s. I went trought many sources and I found some „blank“ areas. 1. First questions are related to Phantoms radar sets. In my search I found almost nothing about ranges (depending on RCS and heigh level of target) , operational modes, scan patterns... of AN/APQ-72, APQ-100, APQ-109 and AN/APG-59 (AWG-10) and differences between each types. I flew the E and D in SEA and then the C model in Europe for four years after. All three models had a radar that could reach out for mapping and beacon targets to 200 miles. Clearly at that range the data presented was very general. Scans were horizontal, +/- 60 degrees from center. C and D offered two bar scan while the E had a three bar scan. APQ-72 (F-4B) and APQ-100 were almost identical for A-A use, the main difference being that the Air Force required the latter to have an adjustable range strobe for bombing (not a very useful feature, actually, given the way it was implemented). Typical max. contact ranges on a MiG in Vietnam seem to be in the 20-30 n. mile range; I've got one account claiming a contact at 33 or maybe it was 35nm, which was unusual. Combat Tree contacts could be at much greater ranges (to be expected given that they're triggering the MiG IFF transponder), at least 60 n. miles according to some accounts I've read. IFF interrogators were later added to the APQ-100 and 109 at least, APX-76 IIRR. Selectable radar ranges were 10, 25, 50, 100 or 200 nm - the APQ-120 added a 5nm range scale. Lock-ons weren't possible with 100 or 200nm selected, for sure in the case of the APQ-100 and probably the others as well. In addition to the wide sweep of 120 degrees, there's also a narrow 60 deg. sweep selectable; there's also a choice of one or _THREE_ (not two; Ed's memory is playing him false here) bar scan. There are a large number of combinations of polarization, pulse length, manual or auto range tracking, gate/aspect, HOJ and other selections possible, which are far too long to list (I've got a copy of the 1F-4C-34-1-1). Walt Bjorneby, who'll hopefully chime in, has stated in the past that the APQ-109 was longer-ranged than the APQ-120, owing to the larger antenna. Basic A-A options were a normal B-scan search and lock-on mode, Boresight, or Gyro Out, the latter mode disabling the antenna stabilization relative to the ground and allowing the WSO to move the antenna relative to the airframe, for high off-boresight lock-ons when maneuvering. This last mode took a fair amount of coordination betwen the two crew compared to boresight, and required a considerable amount of practice. Boresight was originally a wholly rear cockpit selection, but the ability of the front seater to select it and/or start the range strobe/jump over targets (auto acquisition) was improved several times during the war, ultimately ending up with the T.O. 556 F-4E's near-HOTAS setup. AFA I'm aware, the main difference between the APQ-100 and 109 was in the latter's air to ground capability, not A-A. Hopefully "Dweezil Dwarftosser" (John Tomany) will comment, as he has experience maintaining most of these. APG-59 was a high PRF Pulse Doppler (alternatively pulse) set, with a considerably higher average power in PD mode than the earlier sets. Good for head-on detection of look down targets, at least over water, and apparently considerably longer ranged on closing targets than the pure pulse sets, at least when ground clutter wasn't a problem. Friedman's "U.S. Naval Weapons" states that it was credited with detecting a 5 sq. m. target at 60nm, which should be considerably better than the other radars were capable of. 2. Also any infos about AAA-4 IRST are missing. In '72 when I qualified in the airplane, the IRST was deactivated in all aircraft. Removed and replaced by the forward antennas (and maybe the pre-amps) for the RWR in the Air Force a/c. 3. In the case of F-4J, were also VTAS HMS together with AIM-9H used in combat during Linebacker? Or was AIM-9G most advanced Sidewinder used id SEA? J model was USN, so I can't comment. We carried AIM-9J. Red Baron lists no AIM-9Hs fired and states that only the models through the G/J were used. Other sources have claimed that some -9Hs were used, but I've never seen a credible source/official evidence for this. VTAS seems to have been one of those 'nice in theory, but a pain in practice' fits that quickly went away. There are a few people over on r.a.m.n. that have used it, who may be able to answer your question. 4. SUU-16/ 23 gunpods were widely used with many succeses during Rolling Thunder. But never heard that they have been used also in Linebacker. This seems to be interesting, becouse many MiGCAPs (mainly) consisted from F-4Ds and they missiles were unreliable AIM-9E, from second half of 1972 not much better AIM-9J and of course AIM-7E-2. I know that this problem was sometimes solved with adding gun armed F-4E to MiGCAPs instead of F-4Ds. So have been gunpods carried in 1972 by F-4Ds during missins over North Vietnam? Most of the F-4s in SEA flying from Thai bases were E models by '72. There were no D models at Korat in '72 until a deployment from Korea of the 35th TFS. Tahkli got the deployed folks from Seymour Johnson in E models. Udorn which was primary for MiG-CAP flew both Ds and Es. The AIM-9J was quite reliable Well, that's being a bit optimistic. 4 kills in 31 attempts (pK .126), with four of those attempts involving failures to launch, isn't all that much better than the AIM-9B/E. Admittedly, probably four if not more of the misses weren't the fault of the missile but of the inadequate pre-combat testing, which assumed a far greater range for low angle shots, especially at high-Q, than proved to be the case. and the AIM-7E-2 wasn't bad if fired within design parameters, unfortunately training for many didn't really qualify folks in air/air completely. Remember that the MiG-CAP in '72 was working closely with GCI and were better prepared than they had been in the past to engage BVR or at reasonable missile ranges. The Combat Tree F-4Ds with the 432nd at Udorn wouldn't have wanted to carry the gun pod, as it would limit their AIM-7E-2 carriage to two (unless they jettisoned the gun pod), as well as decrease their fuel and up their drag. With an F-4E along it wasn't worth it. The SUU-16/23 pods carried air/air were a short term solution to a short term problem during Rolling Thunder. I wonder if Walt's guys at DaNang ever carried the gun pod on their forays into NVN in 1972? 5. Last question is related to Rivet Haste project F-4Es. How many of these birds were sent to SEA in fall of 1972? Have been also other F-4Es partially upgraded to this standard (556 mod, TISEO, Combat Tree or LES, or their combination? I don't know a hard number, but I'm sure that some of the historical statisticians in the group can help with the Rivet Haste number. I'd estimate about a dozen. Upgrade to TCTO-556, the improved switchology was very rapid and by August virtually all of the Thailand based F-4Es were modified. TCTO-566 was the LES/TISEO structural mod and that was limited to the Rivet Haste (Agile Eagle) birds out of Udorn. Someone else will have to offer numbers of Tree birds. Never had the opportunity to fly one. Thought I had the number of the Rivet Haste birds, but can't seem to find it. The second edition of Tony Thornborough's "The Phantom Story" will likely have it. Michel in "Clashes" says they deployed as an already formed squadron to Udorn and there assumed the identity of the 555th TFS, much to the disgust of the 555th people already there who were transferred to other squadrons. A quick perusal of my xeroxes from the first edition of Thornborough fails to identify their previous squadron designation, but in any case that implies that there may have been as many as 18 to 24 a/c in the deployment, depending on assigned squadron strength at the time. AFAIK the other TREE birds at the time were all Ds - it appears that it was a depot fit. Initially the 432nd had 8 Combat Tree Ds which they got from the 3rd TFW in Korea; around June 1972 they received some attrition replacements. Guy |
#3
|
|||
|
|||
|
#4
|
|||
|
|||
On Wed, 06 Aug 2003 07:20:16 GMT, Guy Alcala
wrote: Removed and replaced by the forward antennas (and maybe the pre-amps) for the RWR in the Air Force a/c. Late 1966 F-4C APR-25 install had the forward pre-amps just behind the antennas, and then later in the F-4D APS-107 had some under the radar package and later moved out to the bottom sides and to the rear on the donkey..... I seem to remember something about the IR package on the radar was replaced with the CW package for the sparrows. So the IR would have been long gone before the APR-25 install? The APS-107D was an excellent, versatile system. Much better launch detect and on some aircraft they could be switched to the forward antennas so the pod jamming didn't bother as much. Just glad I didn't have to work on them six months after they were installed and all the little rf cables had come apart!G |
#5
|
|||
|
|||
Buzzer wrote:
The APS-107D was an excellent, versatile system. Much better launch detect and on some aircraft they could be switched to the forward antennas so the pod jamming didn't bother as much. Just glad I didn't have to work on them six months after they were installed and all the little rf cables had come apart!G Let me see, for comparison sake, would you prefer to ride in my pit downtown with an APS-107D or in an E-model with an APR-36/37, particularly if we are going to be hunting and killing SAM sites? Do you like colored lights better than a clear vector scope display and TDU? Better launch detection than the AS (Azimuth Sector) light and sequence logic of the 36/37? We're not talking about working on them or accessing components here, we're talking about getting easily interpretable missile threat warnings in a combat environment. Ed Rasimus Fighter Pilot (ret) ***"When Thunder Rolled: *** An F-105 Pilot Over N. Vietnam" *** from Smithsonian Books ISBN: 1588341038 |
#6
|
|||
|
|||
Ed Rasimus wrote:
Let me see, for comparison sake, would you prefer to ride in my pit downtown with an APS-107D or in an E-model with an APR-36/37, particularly if we are going to be hunting and killing SAM sites? Do you like colored lights better than a clear vector scope display and TDU? Better launch detection than the AS (Azimuth Sector) light and sequence logic of the 36/37? We're not talking about working on them or accessing components here, we're talking about getting easily interpretable missile threat warnings in a combat environment. Well, speaking as a former ECM tech on the F-4E, most pilots would seem to prefer having a coffee cup holder than an ECM suite that they actually have to know how to use... ....and you wouldn't *believe* how snippy some of those guys got when we loaded ALQ-119 and -131 pods on the planes (early 1980s, well after most plane drivers figured out that ECM is a Good Thing in a high-threat environment). -- Remember: Objects in rearview mirror may be hallucinations. Slam on brakes accordingly. |
#7
|
|||
|
|||
Chad Irby wrote:
Well, speaking as a former ECM tech on the F-4E, most pilots would seem to prefer having a coffee cup holder than an ECM suite that they actually have to know how to use... Unfortunately, you're all too right. The date in your next paragraph explains why. ...and you wouldn't *believe* how snippy some of those guys got when we loaded ALQ-119 and -131 pods on the planes (early 1980s, well after most plane drivers figured out that ECM is a Good Thing in a high-threat environment). In the early '80s we'd been non-combatant for about ten years. We fired up the ECM and RWR for serious only for a Red Flag deployment and the written Stan/Eval test questions for the annual TAC check were all from a study guide. I had the same issue when flying the F-4 out of Torrejon, post-Vietnam. I'd wait after take-off for the WSO to turn on the RWR, usually in vain. I'd wait for the WSO to reach out with the radar and search for traffic that had been called by departure, usually in vain. We carried the 101 or 119 the whole time I was at Torrejon, bolted in the left forward missile well. Never allowed to turn it on in peace-time---"you'll compromise the programs" or "you'll put RAPCON off the air". Motivation to study without a threat or an opportunity to practice will deteriorate. You can believe that we knew exactly what the RWR was doing in the Hunter/Killer mission. And, we didn't object too much to dragging the ALQ-87 or 101 around, even though we never turned it on (it interferred with the Weasel's stuff). The pod was a last ditch aid to SAM evasion when face-to-face with a missile airborne. Now, the guys know exactly what the value is and they have lots of opportunity to practice. Ed Rasimus Fighter Pilot (ret) ***"When Thunder Rolled: *** An F-105 Pilot Over N. Vietnam" *** from Smithsonian Books ISBN: 1588341038 |
#8
|
|||
|
|||
On Wed, 06 Aug 2003 19:40:46 GMT, Ed Rasimus
wrote: Buzzer wrote: The APS-107D was an excellent, versatile system. Much better launch detect and on some aircraft they could be switched to the forward antennas so the pod jamming didn't bother as much. Just glad I didn't have to work on them six months after they were installed and all the little rf cables had come apart!G Let me see, for comparison sake, would you prefer to ride in my pit downtown with an APS-107D or in an E-model with an APR-36/37, particularly if we are going to be hunting and killing SAM sites? Do you like colored lights better than a clear vector scope display and TDU? Better launch detection than the AS (Azimuth Sector) light and sequence logic of the 36/37? In the 1 1/2 year period between the introduction in SEA of the APS-107D and the APR-36/37 which would you have preferred? The APS-54, Vector 4, pre-qual/qual APR-25/26 or APS-107D? Especially if you knew the APS-107D detected missile launch the same way as the year and a half in the future APR-36/37? We're not talking about working on them or accessing components here, we're talking about getting easily interpretable missile threat warnings in a combat environment. We're talking debriefing hundreds of crews. A small percentage complained at first and wished for their old APR-25/26. Over time the complaints went down and some even liked the system... |
#9
|
|||
|
|||
I remember the D radar having about 20-25% better range than the E.
the E wasn't all that bad; ran about 50-60 miles on other F4s over water. Our 390TFS Ds could pickup tankers at 75 miles over Thailand. (Cherry anchor) I had a USN F4J pilot in my back seat one night gunship escort mission ( can't for the life of me remember why)and he marveled at the radar pickup. I asked him why he thought it was soo good when he was flying the J model. He told me after about 4 'standard' carrier landings the radar wasn't so hot anymore. One problem we had with th E was overheating on the ground at DaNang in the summer trying to run bit checks taxiing out. So we left it in standby and did them airborne. AFIK we never took a gun pod North. The O6s had an E with a CL drop and 2 SUU23s on the wings but I don't think anyone below full bird got to fly it. We did hang SUU23s on our Ds for in-country work. Going North it was CL, mers, ters sometimes, AIM9s and AIM7s and a jammer pod, usually in the rt fwd Sparrow well. Ed's on the money on the 36/37 RHAW gear - I monitored the audio and kept an eye on the AZ strobe when the audio sounded interesting. As for over-all radar performance TAC blew it when they went to the storage tube instead of a straight CRT. They threw away at least 3 db performance. AMAF the average D was about equal to our F102As at RG AFB. (We had the best radar people I ever met in the USAF). We could pick up 135s and B52s well over 100 miles over land. FWIW a CRT will let a trained eye pick up a target as low as minus 3 db compared to the average noise level - because it's there all the time and the noise jumps around. In the storage tube the average noise level becomes the cut-off level and you have a nice clean scope and threw away maybe 10% of your range capability. Also - dropping IRSTS was really dumb. I used the Deuce's IR system and while it had bugs (LN2 leaks, usually) when it was working it was superb. Very flexible, very sneaky, very good at low level - TAC F100D low level. BTW every fighter I flew except the F86F had AI radar in it so I was no cherry when I got in the F4 - by then I had about 3000 hours pushing a TV around the sky. Walt BJ |
#10
|
|||
|
|||
If your WSO didn't do RHAW checks and use the radar to clear for traffic,
you should have busted him for stupidity. Les F-4C(WW),D,E,G/AC-130A/MC-130E EWO retired "Ed Rasimus" wrote in message ... Chad Irby wrote: Well, speaking as a former ECM tech on the F-4E, most pilots would seem to prefer having a coffee cup holder than an ECM suite that they actually have to know how to use... Unfortunately, you're all too right. The date in your next paragraph explains why. ...and you wouldn't *believe* how snippy some of those guys got when we loaded ALQ-119 and -131 pods on the planes (early 1980s, well after most plane drivers figured out that ECM is a Good Thing in a high-threat environment). In the early '80s we'd been non-combatant for about ten years. We fired up the ECM and RWR for serious only for a Red Flag deployment and the written Stan/Eval test questions for the annual TAC check were all from a study guide. I had the same issue when flying the F-4 out of Torrejon, post-Vietnam. I'd wait after take-off for the WSO to turn on the RWR, usually in vain. I'd wait for the WSO to reach out with the radar and search for traffic that had been called by departure, usually in vain. We carried the 101 or 119 the whole time I was at Torrejon, bolted in the left forward missile well. Never allowed to turn it on in peace-time---"you'll compromise the programs" or "you'll put RAPCON off the air". Motivation to study without a threat or an opportunity to practice will deteriorate. You can believe that we knew exactly what the RWR was doing in the Hunter/Killer mission. And, we didn't object too much to dragging the ALQ-87 or 101 around, even though we never turned it on (it interferred with the Weasel's stuff). The pod was a last ditch aid to SAM evasion when face-to-face with a missile airborne. Now, the guys know exactly what the value is and they have lots of opportunity to practice. Ed Rasimus Fighter Pilot (ret) ***"When Thunder Rolled: *** An F-105 Pilot Over N. Vietnam" *** from Smithsonian Books ISBN: 1588341038 |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
FA: Vietnam The Helicopter War Large HC Book 189p | Disgo | Aviation Marketplace | 0 | February 6th 04 05:19 PM |
Dogfights in Vietnam | Mike | Military Aviation | 11 | July 30th 03 09:47 PM |
Australia tries to rewrite history of Vietnam War | Evan Brennan | Military Aviation | 34 | July 18th 03 11:45 PM |
Trying to make sense of Vietnam air war | Otis Willie | Military Aviation | 0 | July 6th 03 11:13 PM |
Vietnam search to continue to find remains of Waterford pilot | Otis Willie | Military Aviation | 0 | July 2nd 03 10:30 PM |