The Pilot Factor

[GregP]

Ditto from here. AIrcraft are incredubly strong, especially the military variety. They aren't shabbily built.

The Planes of Fame flies the only remaining authentic Mistubishi A6M-5 Model 52 Zero ... actually the only Zero of any sort flying on the original Japanese engine (and prop). It is NOT built badly at all. In fact, the quality is very good. Until it receives battle damage, it is as strong or stronger than US aircraft.

But since the metal is much thinner, it takes fewer hits to cause critical damage. That is a consequence of choosing a low-horsepower engine to power it, not a consequence of poor build quality.

 

[GrauGeist]

I think the point Garyt is making, is that towards the end of the war, the quality control was not the same as it was in the early years.

This has been seen in German aircraft as well, and due to similar circumstances. While the aircraft weren't "falling apart" after they were coming off the assembly line, the finish quality was not as as high as it could have been (or had been in earlier years), due to the rush.

Also, once in the field, they didn't have the luxury of a secure rear area to R&R the machines as was needed, but patched them up and sent them back out as best as they could. And unlike Europe, certain areas of South Pacific operations were extremely harsh on the aircraft due to the coral dust and humidity.

 

[FLYBOYJ]

I think the point Garyt is making, is that towards the end of the war, the quality control was not the same as it was in the early years.

This has been seen in German aircraft as well, and due to similar circumstances. While the aircraft weren't "falling apart" after they were coming off the assembly line, the finish quality was not as as high as it could have been (or had been in earlier years), due to the rush.

Also, once in the field, they didn't have the luxury of a secure rear area to R&R the machines as was needed, but patched them up and sent them back out as best as they could. And unlike Europe, certain areas of South Pacific operations were extremely harsh on the aircraft due to the coral dust and humidity.

Agree 100%, but his words were "falling apart." If one is going to make a claim like that outside of obvious semantics, be ready to back it up.

It's like me saying, "all Japanese aircraft were junk." I think we all know different!!!

 

[Garyt]

I think the point Garyt is making, is that towards the end of the war, the quality control was not the same as it was in the early years.

This has been seen in German aircraft as well, and due to similar circumstances. While the aircraft weren't "falling apart" after they were coming off the assembly line, the finish quality was not as as high as it could have been (or had been in earlier years), due to the rush.

Yes indeed Graugreist, that is what I meant.

I was speaking metaphorically, as I also do not believe my cough syrup could indeed has served as aviation fuel for the Japanese.

I do recall reading somewhere, though I am not sure of the source, of landing gear failing upon the landing of a few late war Japanese planes, and this being blamed on the more quality and metallurgy of the late war Japanese aircraft industry.

 

[FLYBOYJ]

I do recall reading somewhere, though I am not sure of the source, of landing gear failing upon the landing of a few late war Japanese planes, and this being blamed on the more quality and metallurgy of the late war Japanese aircraft industry.

I think you'll find that all combatants through out the war had, at one time or another, issues with heat treatment during production. Unless specifics are identified, this is a broad brush statement.

 

[Garyt]

I'm not sure of the original source for this, but this has also been reposted from the original source to this forum:

Hayate1 codenamed 'Frank' by the Allies is generally regarded as the best Japanese fighter of the World War II period. Though Hayate was primarily used as a fighter it served in bomber capacity as well. Due to it's advanced direct-injection engine Hayate was able to outmaneuver and outclimb it's American counterparts, the P-47N Thunderbolt and the P-51H Mustang.

Ki-84 was not without problems. Due to the war time shortages and increasingly poorer quality control meant that Japanese pilots never knew how their plane was going to behave. For instance poor treatment of the high-strength steel meant that the landing gear could simply snap upon landing.

Several advanced models were introduced. Ki-84-II and Ki-106 were attempts to build the Hyate using wood as the steel shortages were extreme during the war. Ha-45 and Ha-44 were fitted with a 2,000 and 2,500 HP engine.

A total of 3,514 Hayates were produced. Used over China and Phillipines, in 1944-1945.

Seems the sub "embargo" also caused problems with finished quality.

 

[pbehn]

What difference does a G suit make? Does it make for example a sustained 7 G possible where it isnt without one.

 

[FLYBOYJ]

Again, a broad brush possibly based on isolated incidents with no further specifics. From Wiki..

"Compounding reliability problems were the Allied submarine blockade which prevented delivery of crucial components, such as the landing gear. Many further landing gear units were compromised by the poor-quality heat treatment of late-war Japanese steel. Many Hayates consequently suffered strut collapses on landing. Further damage was caused by inadequately trained late war pilots."

"poor-quality heat treatment of late-war Japanese steel"

Again, without specifics, this is just speculation. I've been involved with metal heat treatment and for the most part it's pretty cut and dry if your ovens are working properly and follow quench times. If the alloying material has issues to start with then no matter how well you control the heat treat process, you'll have problems, and again all combatants had their share of issues with this.

 

[BiffF15]

What difference does a G suit make? Does it make for example a sustained 7 G possible where it isnt without one.

Pbehn,

The G suit I flew with gave a guy about two G's more and in my opinion helped with sustained G's as well. The Blue Angels fly without G suits and the Hornet has a normal G limit of 7.3 (IIRC).

Cheers,
Biff

 

[Garyt]

If the alloying material has issues to start with then no matter how well you control the heat treat process, you'll have problems, and again all combatants had their share of issues with this.

I would think that the Japanese would have had problems with the alloying materials due to shortages caused by the strangulation of the Japanese economy by sub warfare. And I think they would have problems above and beyond any other major nations of WW2, the only ones in a remotely similar situation would be late war Germany (though not an island nation, so not the same), or Britain at the pinnacle of success of the U-Boat campaign, though Britain was not both strangled from sea at the same time it's production facilities were being intensely bombed. Or so at least I have read in different sources, broad-brush as they may be.

I think finding any true specifics on this though will be virtually impossible, at best a needle in the haystack type chase.

 

[FLYBOYJ]

I would think that the Japanese would have had problems with the alloying materials due to shortages caused by the strangulation of the Japanese economy by sub warfare. And I think they would have problems above and beyond any other major nations of WW2, the only ones in a remotely similar situation would be late war Germany (though not an island nation, so not the same), or Britain at the pinnacle of success of the U-Boat campaign, though Britain was not both strangled from sea at the same time it's production facilities were being intensely bombed. Or so at least I have read in different sources, broad-brush as they may be.

I think finding any true specifics on this though will be virtually impossible, at best a needle in the haystack type chase.

Then that would have effected all steel production, not just one design.

Here's a link about the Frank and some comments made about it's quality.

"The performance and reliability of production Hayates was seldom as good as that of the service test machines. As the quality of the workmanship steadily deteriorated, the performance of the Hayate steadily declined as production progressed, with later machines having successively poor and poorer performance and mechanical reliability. The hydraulic and fuel pressure systems were both poorly designed and were subject to frequent failures. The wheel brakes were notoriously unreliable, and the metal of the landing gear struts was often inadequately hardened during manufacture, which made them likely to snap at any time. This caused many Hayates to be written off in landing accidents, without ever having been damaged in combat."

Nakajima Ki 84 Frank

The text shows no references...

I liken this to stories we hear about the Fw 200 and how it was prone to failures of it's fuselage during landing. The German themselves confirmed this issue with the aircraft but you know how many were actually lost due to the fuselage failing? About 8.

I think we could go around on this and show just about any mass produced WW2 aircraft with manufacturing issues, the point here is despite the diminishing quality of Japanese aircraft at the end of the war, they were certainly not falling out of the sky (I do recognize the semantics). Although not to the standards of US Aircraft with regards to production quality, aircraft like the Ki 84 were still dangerous if flown by the right individual.

 

[pbehn]

Heat treatment depends on chemical analysis and chemical analysis depends on some rare and difficult to obtain elements and quality control. Steelmaking has changed vastly in the postwar years. I doubt seriously that the japanese couldnt perform the heat treatment required, more likely they couldnt source rare alloying elements or due to shortage of fuels were obliged to accept "heats" that should have been rejected. A similar problem to the Me262 turbine blades, their failure could be blamed on incorrect heat treatment if you like, the real problem was Germany couldnt get the metals they wanted.

 

[FLYBOYJ]

Heat treatment depends on chemical analysis and chemical analysis depends on some rare and difficult to obtain elements and quality control. Steelmaking has changed vastly in the postwar years. I doubt seriously that the japanese couldnt perform the heat treatment required, more likely they couldnt source rare alloying elements or due to shortage of fuels were obliged to accept "heats" that should have been rejected. A similar problem to the Me262 turbine blades, their failure could be blamed on incorrect heat treatment if you like, the real problem was Germany couldnt get the metals they wanted.

The landing gear was more likely mild steel, 4130 or 4140. Not to difficult to heat treat

 

[Garyt]

aircraft like the Ki 84 were still dangerous if flown by the right individual.

That I do not doubt one little bit. Finding the "right" individual at late stages of the war though became progressively tougher.

 

[pbehn]

The landing gear was more likely mild steel, 4130 or 4140. Not to difficult to heat treat

Mild steel is very easy to heat treat, like I said if the Japanese were struggling for fuels and minerals the basic metal may well have been substandard, de slagging and refining of iron to steel can be termed "heat treatment". Even today companies in financial trouble have ended up on the rocks by cutting corners, "heat treatment" can become a cover all for general sub standard manufacture. Also in this era heat treatment was an extremely skilled job requiring years of training, temperatures were estimated by eyesight and there was no UT, RT and little DP and MP testing. I know nothing about this particular AC, just saying, on the other side many in the west had the opinion that Japanese couldnt make anything of quality so any failure would be blamed on that rather than just a hard landing.

 

[GrauGeist]

And this brings us back to the pilot factor...

If the aircraft had marginal material quality but a good, experienced pilot, it may have held up well enough. However, you have an influx of inexperienced pilots being rushed through training and sent to the front and now that same aircraft will fail under the inexperience (hard landings, ground loops, improper proceedures, etc.).

So now the numbers of "failures" start climbing on the books and the fault may not lay entirely on the aircraft.

 

[bobbysocks]

new and inexperienced pilots are hard on landing gear ... even ones in perfectly good working order.

 

[FLYBOYJ]

Mild steel is very easy to heat treat, like I said if the Japanese were struggling for fuels and minerals the basic metal may well have been substandard, de slagging and refining of iron to steel can be termed "heat treatment". Even today companies in financial trouble have ended up on the rocks by cutting corners, "heat treatment" can become a cover all for general sub standard manufacture. Also in this era heat treatment was an extremely skilled job requiring years of training, temperatures were estimated by eyesight and there was no UT, RT and little DP and MP testing. I know nothing about this particular AC, just saying, on the other side many in the west had the opinion that Japanese couldnt make anything of quality so any failure would be blamed on that rather than just a hard landing.

Agree - the Japanese more than had enough skill and technology to heat treat mild steel which was used extensively in aircraft construction, not only in all metal aircraft but in fabric aircraft as well. 4130 steel tube was the basic frame work of most if not all fabric aircraft of the period. There's no exotic alloys in 4130 carbon steel - Carbon, Chromium, Manganese and Molybdenum if I remember correctly

 

[FLYBOYJ]

And this brings us back to the pilot factor...

If the aircraft had marginal material quality but a good, experienced pilot, it may have held up well enough. However, you have an influx of inexperienced pilots being rushed through training and sent to the front and now that same aircraft will fail under the inexperience (hard landings, ground loops, improper proceedures, etc.).

So now the numbers of "failures" start climbing on the books and the fault may not lay entirely on the aircraft.

new and inexperienced pilots are hard on landing gear ... even ones in perfectly good working order.

Agree all the way around

 

[pbehn]

Agree - the Japanese more than had enough skill and technology to heat treat mild steel which was used extensively in aircraft construction, not only in all metal aircraft but in fabric aircraft as well. 4130 steel tube was the basic frame work of most if not all fabric aircraft of the period. There's no exotic alloys in 4130 carbon steel - Carbon, Chromium, Manganese and Molybdenum if I remember correctly

Chromium Manganese and Molybdenum are not exotic but I think may be hard to source in Japan. I think the discussion is a bit off target, I have seen 4 warbirds undercarriage fail, all because they didnt lock out. I cannot imagine a landing hard enough to bend or snap the steel in a leg without the whole of the rest A/C being a write off, like the passenger plane that landed really hard and punched the undercart struts straight through the wing.