Plexiglass quality differences in the game between different airplanes.

[klebor]

I was reading some older Game Updates discriptions and i have found this:

 

Han: Update 2.004

Quote

3D Models

24. P-40 cabin plexiglass quality increased;

and

Han: Update 2.005

Quote

Dear Pilots!

 

The work on version 2.005 is finished and we present it to you. It doesn't bring as many changes as the last version did, but it does bring a new, long awaited Collector Plane – the Soviet Yak-1b fighter. My personal feelings about this plane is that it is a pleasure to fly and it completes a maneuver strictly and precisely, be it a barrel roll or a loop. It is highly maneuverable, handles predictably during all flight phases and doesn't make a pilot life more miserable than it has to be. Its powerful weaponry gives it a kick while the pilot will enjoy the excellent field of view in spite of Soviet plexiglass quality being inferior to German or American materials. A Yak-1b pilot is significantly more protected from small caliber bullets and shell fragments when compared to earlier fighters. And the most important thing is that it is beautiful! 

I also knew Soviet plexiglass quality was inferior to German or American material and Soviet pilots notoriously fly with open canopies to have clearer view what is being described in some historical sources but i did't know our game models that.

On the other hand i fly Soviet, German, American and British planes in equal proportions in MP but i did'n notice any difference in plexiglass quality. I fly with closed canopy in every plane and i have clear view. I use medium graphic settings.

Do i miss something? Did plexiglass quality differ more in previous versions before i start to play? This quotations are from the end of 2016.

 

[Finkeren]

I think the difference is there, but not very apparent. Overall the canopies on Soviet aircraft just seem "dirtier" to me.

 

AFAIK, the main problem with the quality of the Soviet-produced plexiglass was that it tended to quickly darken and take on a yellowish color and become less transparent with use. 

 

The tendency for VVS pilots to fly with the canopy open or removing the sliding part of the canopy altogether had nothing to do with the transparency of the plexiglass but was down to two factors: 

 

1. The fear of not being ably to pry open the canopy in an emergency. Soviet aircraft generally didn't have explosive emergency releases for the canopy, and the fear of being trapped inside a stricken aircraft was very real (and well represented in the game as well) This fear was especially common early in the war, and open or missing canopies are very often seen especially on MiG-3s in 1941-42.

 

2. The buildup of exhaust gasses or other noxious fumes inside the cockpit due to poor sealing of the engine compartment. Apparently this was a particularly big problem on the La-5. But before you go blame it on poor Soviet production quality, the Hawker Typhoon suffered from the exact same problem.

 

 

[Feathered_IV]

I did wonder about that a bit.  Authors sometimes mention Soviet era plexiglass, but don't elaborate on exactly how it was inferior.  Whether it was foggy, scratchy, yellow, distorted or whatever.  I used to work in the plastics industry, so I'd be interested to know.

[Brano]

Soviets did first synthetisation of plexiglass (in russian oрганическое стекло) in 1936 by  НИИ пластмасс (Научно-исследовательский институт пластических масс).

They faced usual problems with thermoforming of polymethyl methacrylate material.

1. Technological discipline and process parameters = when not under control, during forming there were microcracks created in concave areas and small radiuses leading to "foggy" effect. Either forming temperature was NOK, or closing speed of the press too fast etc.

2. Material composition = it didnt have UV protection component so it got "yellowish" after prolonged exposition to sunlight

[Art-J]

1 hour ago, Brano said:

2. Material composition = it didnt have UV protection component so it got "yellowish" after prolonged exposition to sunlight

 

As can be still seen today in these museums on eastern side, which have any Soviet-built WWII-era planes stored and deteriorating outdoors. These, which didn't get their plexi restored (replaced) as some point, often have canopies or windscreens matt yellow/brown, without any transparency whatsoever.

Though as a bit of curiosity, I've noticed the same sometimes applies to more modern designs. In one of museums here in Warsaw, you can see original MiG-15 with canopy in very good condition despite standing in the open for a few decades, a couple of meters from MiG-23MF, withdrawn from service in '99, with its windscreen already completely flat.

[RedKestrel]

3 hours ago, Finkeren said:

I think the difference is there, but not very apparent. Overall the canopies on Soviet aircraft just seem "dirtier" to me.

 

AFAIK, the main problem with the quality of the Soviet-produced plexiglass was that it tended to quickly darken and take on a yellowish color and become less transparent with use. 

 

The tendency for VVS pilots to fly with the canopy open or removing the sliding part of the canopy altogether had nothing to do with the transparency of the plexiglass but was down to two factors: 

 

1. The fear of not being ably to pry open the canopy in an emergency. Soviet aircraft generally didn't have explosive emergency releases for the canopy, and the fear of being trapped inside a stricken aircraft was very real (and well represented in the game as well) This fear was especially common early in the war, and open or missing canopies are very often seen especially on MiG-3s in 1941-42.

 

2. The buildup of exhaust gasses or other noxious fumes inside the cockpit due to poor sealing of the engine compartment. Apparently this was a particularly big problem on the La-5. But before you go blame it on poor Soviet production quality, the Hawker Typhoon suffered from the exact same problem.

 

 

As far as soviet planes being dirtier... I noticed a bunch of smudges on my screen when I zoomed in on my MiG's gunsight last night. Tried to wipe off the monitor display, and realized the smudging was on the canopy in game!

[Sgt_Joch]

I have not tested lately, but when flying the La-5, it was easier to spot and track bogeys when flying with an open canopy than a closed one. However, now that it is difficult to open the canopy in flight, it is less tactically useful.

[[APAF]VR_Spartan85]

Yeah you have to take off with the canopy open or slow down enough to open it during flight and if you want to close it again.  Very noisy though

i wish we had the ‘heat like in helmet’ option... I would assume there was at least some sound dampening with their head gear on???

[HagarTheHorrible]

There was a reason that the Germans used flat plate glass for the canopies of the 109 etc.

 

Distortion was a serious issue with early Perspex, simple, single plane, curves aren't to troubling, but " blown" compound curves were a serious issue with stress fractures, resultant fogging and distortions of view.

[Finkeren]

38 minutes ago, HagarTheHorrible said:

There was a reason that the Germans used flat plate glass for the canopies of the 109 etc.

 

Distortion was a serious issue with early Perspex, simple, single plane, curves aren't to troubling, but " blown" compound curves were a serious issue with stress fractures, resultant fogging and distortions of view.

 

Did any Soviet fighter before the La-9 even use blown canopy? 

[HagarTheHorrible]

Less the entire canopy, more the front fixed part next to the front, often, armored glass panel, although that said I didn't really use the right word, as you correctly pointed out, less blown more compound ( curving in two directions at the same time).  It's interesting to note that even post war aircraft, like the Mig 15 , employed tricks and  techniques to reduce manufacturing distortion by simplifying shapes and curves rather than employing one single sheet for the main canopy.  If I remember correctly I think the SE5 was one of the first combat aircraft to employ a Perspex hood, of sorts, but it was universally disliked and usually removed when fitted.

[danielprates]

My country's airforce bought several Gloster Meteors from England in the early 50s (legend goes they were bought for a shipment of cotton, at a time the American government were trying to push the f-86 for a high price in cash). They can still be seen all over, in public displays, the first one on the list below is in my hometown. They give good  example on what happens to tended or untended Plexiglas: the ones that got some care (polish? probably just that) are still pristine today, whereas the ones left unattended developed that opaque characteristic that arises from too many scratches and the natural yellowing effect that the sun has on such materials. I am imagining that those Plexiglas parts represented the best that the industry could make in the 40s. 

 

Edited June 16, 2018 by danielprates

[unreasonable]

I suspect dust build up from natural static has something to do with those photos too.  Plastic sheets of any kind seem to love dust. 

[Danziger]

[-TBC-AeroAce]

Ok it is well known that plastic goes off due to UV damage. I have seen this happen to cheap products in less than a year.

 

But in this sim clarity aside we are not interested in the long term damage but more the general durability. Would it have been more easy to scratch VVS plastic compared it's contemporaries? 

[HagarTheHorrible]

20 minutes ago, AeroAce said:

Ok it is well known that plastic goes off due to UV damage. I have seen this happen to cheap products in less than a year.

 

But in this sim clarity aside we are not interested in the long term damage but more the general durability. Would it have been more easy to scratch VVS plastic compared it's contemporaries? 

 

Scratch resistance is a bt of a problem.  Make it too soft and it scratches easily from dust, grit and general usage.  Make it more scratch resistant and you end up with a product that is not only harder to produce in the desired shape but is also far more prone to stress fractures from the constant vibration.  While not always apparent, you can almost guarantee that they make themselves visible when least desirable.

 

I imagine the typical operating enviroment for aircraft in either the Soviet Union, at the time or indead in the desert was particularly harsh whether it be dust or ice particles. Maybe less of an issue for aircraft operating from prepared concrete runways ?  I would have thought that the canopies of Russian aircraft, in particulaar, got chewed up pretty quickly with aircraft operating from rough strips and that the canopy that came with the aircraft was the one that stayed with the aircraft until the aircraft was written off.

 

If I where to hazard a guess I wouldn't be surprized that the 109 canopy is pretty much entirely made from glass rather than perspex.

[Brano]

You can get "yellowish" product right from the production. There are several root causes, most numeric were dirty mold and overheating of plexiglass sheet.

[NZTyphoon]

Note that the curved windscreens used on most early Spitfire VBs (the ones with the separate bullet-resistant glass plate) also suffered from some distortion through the sides: Jeffrey Quill, who was Supermarine's test pilot, complained about this distortion after spending some time in operational service on a Spitfire squadron during the Battle of Britain: these observations led to the later windscreen with flat side glass and integral bullet-resistant glass. ( I couldn't say how bad the distortion was, but the attached photo of a restored Spitfire Ia shows some slight distortion, that could be crucial during combat)

Also of interest is the green tint to the armoured glass that does seem to be genuine: also attached are photos of two properly restored, battle of France era Spitfire Ias, both of which have the same tint. More research needed, perhaps?

[ZachariasX]

6 hours ago, NZTyphoon said:

also attached are photos of two properly restored, battle of France era Spitfire Ias

 

I‘ve seen one these marvels in the hangar in Duxford. They are absolutely no comparison to the crate the put up in the Imperial War Museum n London. The new ones have these beautiful, clear windows, whereas the original that is „as is“ from the airfield shows a dramatically more distorted vision through the canopy, this aside from the dust on it.

 

I am positive that no Spitfire back then came even close to the clarity of the glass that is on the beautiful „J“.

[HagarTheHorrible]

Sodium content makes the glass greener, the thicker the glass the more apparent.  Increasing it's bullet resistance, (hardening ?) may have also lead to a higher sodium content ?  It might have actually been beneficial as well, providing a bit of contrast to the gunsight.

 

I agree that it could be a bit misleading comparing modern replacement parts, on restored aircraft, to the originals.  Manufacturing has come along way since the 1940's,  modern float glass is great but if I want old, imperfect glass ( cheap and crappy greenhouse glass)  for furniture restoration projects, it's difficult to source and expensive.

Edited June 20, 2018 by HagarTheHorrible

[unreasonable]

9 hours ago, NZTyphoon said:

Note that the curved windscreens used on most early Spitfire VBs (the ones with the separate bullet-resistant glass plate) also suffered from some distortion through the sides: Jeffrey Quill, who was Supermarine's test pilot, complained about this distortion after spending some time in operational service on a Spitfire squadron during the Battle of Britain: these observations led to the later windscreen with flat side glass and integral bullet-resistant glass. ( I couldn't say how bad the distortion was, but the attached photo of a restored Spitfire Ia shows some slight distortion, that could be crucial during combat)

Also of interest is the green tint to the armoured glass that does seem to be genuine: also attached are photos of two properly restored, battle of France era Spitfire Ias, both of which have the same tint. More research needed, perhaps?

 

 

 

 

Lovely photos of the prettiest Spitfire (QV) with it's cute little nose.  Some more on QV here for those interested:  https://www.iwm.org.uk/history/the-spitfire-lost-for-almost-50-years

[303_Bies]

On 6/15/2018 at 9:52 AM, sereme1 said:

in spite of Soviet plexiglass quality being inferior to German or American materials.

Theoretically the difference should be implemented if Han stated so.

But to be honest i didn't notice a difference between Soviet and American/German canopies transparency. I'll check today for sure.

[ZachariasX]

5 hours ago, HagarTheHorrible said:

Sodium content makes the glass greener, the thicker the glass the more apparent.  Increasing it's bullet resistance, (hardening ?) may have also lead to a higher sodium content ?  It might have actually been beneficial as well, providing a bit of contrast to the gunsight.

 

The green tint are iron oxide impurities. Pure silica glass doesn‘t have this tint (it is clear), but this „pure“ glass has such a high melting temperature that it even was suitable for window panels to be used for the Space Shuttle, it withstands over 1‘400* centigrades.

 

To be able to make glass (from sand) in the first place, you use sodium to make gass „softer“. The more baking powder you add when meling sand (basically), the lower the melting temp will be and it becomes progressively easier making glass panels (or anything glass). The „softer“ the glass, the less tolerant to the environment it will be. Such cheap glass will turn white in your dishwasher, as it can be dissolved by the hot water and the detergent. Glass artifacts from a thousand years ago perished in the ground. Were they of silica glass, they would still be with us.

 

The toughening of the glass is done by other means, namely compressive stress.

 

Thus, the greener the window, the cheaper material used for the window. The thicker the glass, the more apparent the coloring. Today, you can shop them in any color shade you like. This is done just by starting with pure silica and adding different ions. Or you can also shop for white/clear glass.

 

[LukeFF]

6 hours ago, bies said:

But to be honest i didn't notice a difference between Soviet and American/German canopies transparency. I'll check today for sure.

 

Soviet armored glass has a darker tint to it.

[NZTyphoon]

18 hours ago, ZachariasX said:

 

I‘ve seen one these marvels in the hangar in Duxford. They are absolutely no comparison to the crate the put up in the Imperial War Museum n London. The new ones have these beautiful, clear windows, whereas the original that is „as is“ from the airfield shows a dramatically more distorted vision through the canopy, this aside from the dust on it.

 

I am positive that no Spitfire back then came even close to the clarity of the glass that is on the beautiful „J“.

The windscreens and canopies on the restored Spitfires are probably much closer to what they were like when the aircraft were originally in service in 1940, than they are on an old aircraft that went through several years of operational service service in front-line, secondary and Maintenance Units, before being handed to the museum in 1946 (suffering from 2 accidents while in OTU service): as it is, there's no guarantee that the windscreen and canopy now fitted aren't just old, unserviceable and distorted items that were fitted once the Spitfire was no longer airworthy. To get a better idea, it's better finding good photos of operational Spitfires, such as the one below.

 

According to a Flight article from 1942, Perspex (British name) Plexiglass (original German name, also used by USA) or D.T.D 339A was "even more transparent than glass" : following are the links to the article, describing how the material was formed and moulded. The distortion mentioned by Quill probably came from the need to stretch the perspex to create a compound curve.

https://www.flightglobal.com/pdfarchive/view/1942/1942 - 2014.html

https://www.flightglobal.com/pdfarchive/view/1942/1942 - 2017.html

https://www.flightglobal.com/pdfarchive/view/1942/1942 - 2018.html

Edited June 21, 2018 by NZTyphoon
Spelling

[=EXPEND=CG_Justin]

On 6/18/2018 at 6:48 AM, HagarTheHorrible said:

 

Scratch resistance is a bt of a problem.  Make it too soft and it scratches easily from dust, grit and general usage.  Make it more scratch resistant and you end up with a product that is not only harder to produce in the desired shape but is also far more prone to stress fractures from the constant vibration.  While not always apparent, you can almost guarantee that they make themselves visible when least desirable.

 

I imagine the typical operating enviroment for aircraft in either the Soviet Union, at the time or indead in the desert was particularly harsh whether it be dust or ice particles. Maybe less of an issue for aircraft operating from prepared concrete runways ?  I would have thought that the canopies of Russian aircraft, in particulaar, got chewed up pretty quickly with aircraft operating from rough strips and that the canopy that came with the aircraft was the one that stayed with the aircraft until the aircraft was written off.

 

If I where to hazard a guess I wouldn't be surprized that the 109 canopy is pretty much entirely made from glass rather than perspex.

 

This ^

 

Small particles, over time and "cycles" (takeoff/landing), can be extremely abrasive. Working in the aviation industry, I get a first hand account of what these particle can do. For instance, on our CRJ's, the leading edges of the wing are bare aluminum. If we have to replace a section of the leading edge for any reason, the new section is usually very polished and shiny, while the old section with many many "cycles" logged will feel almost like sand paper because of the amount of abrasion from particulates over time. And this happens to aluminum. Imagine if you will, these particulates being whipped up and blasted back into the plexiglass by a propeller, with the plexiglass being softer then aluminum. Without having lived it and been there, I would speculate that keeping a scratch free windscreen would have been near impossible for either side when using plexiglass. Add to this the addition of using inferior materials and techniques, I can see how this could be a real problem. 

[Arfsix]

Don't be fooled!

          Every fitter, mechanic, and crew chief worth their salt knows that "Brasso" is not for shinning medals or uniform brass, but is for polishing scratches out of aircraft windshields and canopies!   ?

 

 

Edited June 21, 2018 by Arfsix

[unreasonable]

8 hours ago, Arfsix said:

Don't be fooled!

          Every fitter, mechanic, and crew chief worth their salt knows that "Brasso" is not for shinning medals or uniform brass, but is for polishing scratches out of aircraft windshields and canopies!   ?

 

 

 Aarrgh! Sam Browne flashbacks!

[HagarTheHorrible]

https://g.co/kgs/xmvzme

 

Yep, definetly a Sam Brown flashback.

[Sgt_Joch]

Been reading E.R.Hooton, "War over the Steppes: The air campaigns over the eastern front 1941-45", (2016) and came across this:

 

Quote

The petrochemical industry also caused problems for the VVS. When exposed to sunlight the Perspex in aircraft canopies tended to degrade and become opaque - a problem which does not appear to have been overcome until later in the war. Because of this, even in the bitter Russian winter, pilots would fly with open canopies...

 

(pp.21-21)

Edited June 22, 2018 by Sgt_Joch

[NZTyphoon]

On 6/22/2018 at 5:25 AM, Arfsix said:

Don't be fooled!

          Every fitter, mechanic, and crew chief worth their salt knows that "Brasso" is not for shinning medals or uniform brass, but is for polishing scratches out of aircraft windshields and canopies!   ?

 

 

Attached is a page from a Spitfire Ia servicing manual, recommending (an unspecified brand of) metal polish for the windscreen, canopy and rear transparency: note the comments about petrol - presumably, splashes of hot oil or pure glycol could also have adverse affects.

Also attached: a 1938 vintage advertisement from Flight magazine extolling the virtues of 'PERSPEX' SHEET (used on the Hawker Hurricane).

PS: Maybe the developers could provide a can of Brasso (or the Soviet equivalent) and some soft rags in the cockpit so the pilot can clean his windscreen, and canopy before takeoff?

Edited June 23, 2018 by NZTyphoon
PS

[kramer]

I was flying LaGG-3 in very harsh weather and rain and i have noticed the plexiglass of my canopy was decreasing visibility a lot. I prefered to fly with open canopy to spot better (and be able to jump in case of emergency).

Bravo for the developers.

Edited July 9, 2018 by kramer