computing gunsights and SF series

[jet_spud]

hi again,

 

ww2 pilot trying to understand post war jet combat in this brilliant game.

 

when did computing gunsights become standard? do all postwar (say post korea) jets in SF series use a computing gunsight that compensates for "leading a target" or was it in service by one side before the other?

 

does it also come into play on ground targets? though this seems unlikely to me. am sure i flew a MiG downloaded form here the other day and i had sights squarely over a target aircaft but my rounds didn't seem to hit until i got up real close and personal, then kaboom!

[MigBuster]

Depends on Jet e.g. The F-4C had a manually depressed sight but the F-4D had a lead computing sight according to a book I have - so expect TKs jets to have the correct sight for what they used.(you will notice the difference between the F-4C and D anyway)

 

tbh your gonna be leading things anyway in the heat of battle - things happen a lot faster in jet world.

 

No I dont believe the A-G mode is accurate - just strafe - for a start your jet would need to lock onto the ground target (if it has a ground radar even) - cannon is still an unguided weapon and the shells are affected by the environment as soon as they leave the jet at whatever angle/speed/altitude etc - all probably affects it.

 

For precision weapons - see LGB/Walleye/Maverick

Edited August 27, 2009 by MigBuster

[Wrench]

for the AAF, i'd have to guess 1944, when the D Mustangs got the K-14s (maybe Jug N/Ms too??) USN, don't know if the Mk.8s were or not (most likely not)

 

I'd guess approx the same time for the RAF Mk.III "Ace Maker", but I never did find enough info on that one.

 

Don't think the Japanese ever used one, but maybe the Luftwaffe's Revi-16 might have been. Again, I never did find enough data.

 

as for a-g sights, i'm pretty sure they'd be 'fixed' (ie: the cockpit ini may read caged or AG, with the depression built in). I know the K-14's I've done have a seperate a-g sight; a kind of semi-circular ladder thingy that really helps in getting bombs on target. Oddly, when using the HVARs, it reverts back to the guns reticle.

 

Sabres, obviously, were -with that little ranging radar in the nose (and possibly F-80s, too)

 

What I miss on the modern ones is the "V" shaped guide, like we used to see in Falcon 3 & 4

 

wrench

kevin stein

[jomni]

I believe more Western planes had these earlier than the Russian ones.

 

BTW, compared to WW2, the guns are bigger caliber, use explosive shells, and have less ammo.

WW2 era spraying tactics is not advised anymore as only a few shell hits will already kill a plane.

Edited August 27, 2009 by jomni

[+331Killerbee]

There were two Types of Gunsights used durning WWII. They were Reflective and Gyro Sights. The U.S.Navy had two Types of Reflective Gunsights. One was the Mk.8 used first on F4F's. The second was the Mk.9. It was used on all Naval Bomber Types such as the SBD. It had manual "Depress" for Gun's and Bombing. The Mk.18 was a Gyro Sight that was Lead Computing. It was introduced on the F4U. The Mk.18 became the "Grandfather" of the Ferranti Gunsight used on A-1's, A-4's and early F-8's.

 

Rounds Convergence is the Point where the Rounds come to a Point of Impact. Ending with the retirement of the A-4 from service, Pilots could select and choose the Rounds Convergence to their personal Tastes. This was done on the Ground by Ordnancemen by setting Gun Convergence Set Screws on the Gun Chassis of the Gun Rack. Each Gun, no matter the Type (Such as a Mk.12) or Timeframe (WWII,Korea,Vietnam). Pilots regularly had their Rounds Convergence set. This became important with F-86's durning the Korean Conflict. Many times the F-86's would pull G's that would short out the Reflective Gunsights. So, Pilots would use their Round Convergence with Tracers to sight-in their Targets. Many Kills in Korea were done in this fashion.

 

 

The Set Screws in the Gun Chassis worked in the X,Y,Z Axis. So Guns were set to a "Rounds Convergence Pattern" according to the Pilot's tastes. One Pilot might like a "Stright-Line" Pattern either in the X or Z Axis. One Pilot might want his Rounds to "Stack". One might want a "Up and Down" Pattern.....It was all up to the Pilot and could also be set for Mission requirements.

 

This Practice ended with the Retirement of the A-4 from service and the introduction of Multi-Barreled Gatlin Guns. Nowadays, Gatlin Gun Systems have Phenumatic and Hydraulic Actuators that are Computer controlled. The Gun is adjusted according to conditions. ROF of such Gun Systems make adjusting Rounds Convergence something of the Past......

 

 

331KillerBee

Edited August 28, 2009 by 331Killerbee

[Wrench]

THAT's the kind of info I love collecting!!!

 

I'd always assumed (and we all know what happens when you do that), that the convergence/boresights angle were done like vehicle alignments (back in the day); loosen a bolt and slid in a calibrated shim that x thickness = y degrees. I can see where that might not work, of course, given the much heftier bouncing around aircraft get than your average car.

 

So, is it then also safe to assume the the A-1,A-4 and early F-8 were lead computing?

 

wrench

kevin stein

[+331Killerbee]

THAT's the kind of info I love collecting!!!

 

I'd always assumed (and we all know what happens when you do that), that the convergence/boresights angle were done like vehicle alignments (back in the day); loosen a bolt and slid in a calibrated shim that x thickness = y degrees. I can see where that might not work, of course, given the much heftier bouncing around aircraft get than your average car.

 

So, is it then also safe to assume the the A-1,A-4 and early F-8 were lead computing?

 

wrench

kevin stein

 

 

Yhea Kevin,

Much like a Car Chassis. With most Six Gunned Aircraft like a P-51 on the Wing Leading Edges or a F-86 with Six .50 Cals in the Nose. Each Gun could be individually adjusted through the Set Screws. I know We've all seen those early Films of an Aircraft on the Ground firing it's Guns at a Cloth or Paper Target. That's what the Ground Crew is doing there. Adjusting the Rounds Convergence of the Guns....Along with test Firing them. This process was done on a regular scheduled Maintence Inspection. In the case of the A-4's I worked on, It was done every 180 Days.

 

The process is long. In the case of the A-4, There was a whole Manual dedicated for how to set the Aircraft up. And it only had two Mk.12's. The process is not unlike setting up a Shoulder Fired Weapon.

 

First, The Aircraft had to be Zeroed "0" with it's Gunsight. The Aircraft was placed on Jacks and Jacked up until the CG of the Aircraft Level and the Gun Chassis were loose enough so a Ordnanceman could move the Gun in the Chassis by Hand. A Calibrated Rod was placed through the Barrels of the Guns with a Fixture on the Ends of the Rods. These Fixtures had a manual Indicator on them, So when adjusted, The Guns could be lined up for the Zero-ing of the Aircraft. The Aircraft being "Zero-ed" ment that the Guns would fire at a Trijectory stright out from the Aircraft along the same path as the Sight is adjusted to, with no Convergence dialed in.

 

Then came Rounds Convergence Adjustment. It was done with the same Calibrated Rods, but without the Fixtures. In the case of the A-4, A large, Preset Board was placed in front of the Aircraft. The Board was painted and marked like a Large Graph. The Ends of the Rods pointed out on the Graph the Distance of the Round Convergence. The Guns were set accordingly via the Set Screws through the Gun Chassis.

 

Keep in mind, This all came after a 180 day Inspection in which each Gun was tore-down, cleaned, serviced and assembled and placed back into the Aircraft.

 

Once the Rounds Convergence was set "Dry", Then the Aircraft was towed out to a "Live" Firing Area. The Area consisted of the same Graph as a Board, except it was printed on Cardboard and set in a Fixture that compensated for the Angle of the Aircraft's Landing Gear. A very high, Thick Mound of Dirt...More like a Mountian of Earth burm to catch the spent Rounds behind it. This Area is where We'd test Fire Guns to see if our work was right and to test out the Convergence Adjustments.

 

 

The A-1, A-4 and F-8B all had Lead Computing Sights. Most all early Jets starting with the F-80 had "LC" Gunsights. By the End of the Korean War, They were going from Gyro's to Solid-State equipment. Today, HUD's use Microprocessers to do the same thing.

 

 

331KillerBee

Edited August 28, 2009 by 331Killerbee

[+331Killerbee]

Quick Story about the Colt Mk.12's and the F-8.

 

 

When I got to VMFA-235, We still had some Ole' Ordnancemen that were in 235 when they had F-8's. The Max Effective Range of the Mk.12 was alittle over 1800 Meters. They told Me that They used to set the "RC" to 1700 Meters for the Top two Guns. The bottom two were set at 1684 Meters. That's a "RC" Area of 16 Meters.....

 

Roughly the Length of a Mig-21.......

Edited August 28, 2009 by 331Killerbee

[jet_spud]

thanks very much guys - its a lot clearer now. except whats a cage sight

 

i did wonder whether USN/USAAF might have had more advanced gunsights than russian-built aircraft - like those used by the NVAF, because the US seemed to go down the path of more high-tec whilst the russians seemed to prefer faster productiion; almost like a battle of quality v quantity, although in vietnam i guess the US enjoyed the quantity too.

 

i suppose thinking about it, that is the way russia went in ww2 as well, inasmuch as they rapidly out produced the luftwaffe but often at a cost in quality and equipment (air to air radios and gunsights being a good example) certainly in the early and middle years at least, and russian pilots were pretty expendable then.

 

must try and find a book covering these jet conflicts detailing air to air and air to ground weapons, anyone recomend one?

Edited August 28, 2009 by jet_spud

[DaniloE31]

Just want to add my humbly two cent to this discussion:

right now I'm reading the book: "Clashes, Air Combat over North Vietnam 1965-1972".

Referring to the engaments of the F105Ds against the MiG-17s, they report a lot of complaining from the Air Force pilots about the gun sight.

 

It was a Gyro sight, and was obviously set to air-to-ground for default. Unfortunately it took a lot of precious time for switching it to air-to-air, needing 5 (five) switches to be toggled in the right sequence...

So they mostly just fired with a wrong gunsight... many of the Mig kills was achieved this way

 

Danilo

[Fubar512]

thanks very much guys - its a lot clearer now. except whats a cage sight

 

i did wonder whether USN/USAAF might have had more advanced gunsights than russian-built aircraft - like those used by the NVAF, because the US seemed to go down the path of more high-tec whilst the russians seemed to prefer faster productiion; almost like a battle of quality v quantity, although in vietnam i guess the US enjoyed the quantity too.

 

 

Not really. The MiG-17, for example, had a very effective (read that as "accurate") radar-ranging gunsight. It operated on a frequency normally used by AAA radars, therefore, it used to trip the "AAA" warning light on most Western fighters.

Edited August 28, 2009 by Fubar512

[FalconC45]

must try and find a book covering these jet conflicts detailing air to air and air to ground weapons, anyone recomend one?

 

For fighter Air to Air, I'll recommend this http://www.amazon.com/Fighter-Combat-Tactics-Maneuvering-New/dp/0870210599/ref=sr_1_1?ie=UTF8&s=books&qid=1251477337&sr=8-1 this is the simmer's bible imho. It's kinda dry but it was used as a text book in the AFA in Colorado.

 

Falcon

[jet_spud]

cheers for the books recos. going to amazon next....

 

i like the idea that multiple kills can be made by the "spray and pray" method - that fits in well with my general performance in il-2 !

 

can equate with the probs the thunder boys had in nam, cos by heck do i do some fiddling with the blasted sights and weapons too guess thats what they call a realistic combat sim?

 

those NV MiG's were a pretty worthy foe overall it seems, especially the 21's, and they had the advantage of a friendly face when they bailed - presuming they were'nt already toasted of course.....

Edited August 28, 2009 by jet_spud

[+331Killerbee]

thanks very much guys - its a lot clearer now. except whats a cage sight

 

 

The Word Cage or "Caged" refers to two instances. One, For A2A and A2G Missile's Guidence and Control Sections (G&C's). If the G&C of the Missile's Seeker is "Caged", It means that the Seeker is Locked looking straight ahead. "Uncaged" means the G&C is active and Looking for it's Target in the Seeker. The Missile's FOV is unlocked.

 

"Caged" as referenced to Gunsights means that there is no "Depress" or Adjustments. Straight ahead. What You see through the Gunsight is what You get. Any Gunsights that are not Lead Computing and don't have a Bombing Depress are "Caged" Sights.

[jet_spud]

thanks for the info on caged sights 331.