The Zero's little-known weakness

[Sea Serpent]

I know that on occasion, in combat flight sims, I’ve been just about to pull lead on a maneuvering opponent (at 90 deg bank) and it appeared they’ve kicked in a slip toward the low wing, throwing off my lead, and slicing down under my nose.  In other words, they’re essentially just taking themselves out of plane using a slip.  I guess since they’re slowing down a bit from the airbraking effect, they are also effectively decreasing their turn radius relative to the attacker’s.  Could something like this be what Grungymonkey is referring to?

[GrungyMonkey]

2 hours ago, ZachariasX said:

You should really close that book and never open it again. I'll leave it at that now.

Calm down there dude, I was playing devils advocate for a silly physics idea, not advocating eugenics.

Edited October 5, 2023 by GrungyMonkey

[GrungyMonkey]

35 minutes ago, Sea Serpent said:

Could something like this be what Grungymonkey is referring to?

Even if my suggestion was right, it wouldn't really be a noticeable improvement in radius.

What it sounds like you're describing is them ruddering into an escape-dive, which is perfectly normal.

[ZachariasX]

51 minutes ago, Sea Serpent said:

Could something like this be what Grungymonkey is referring to?

I haven't considered that point as such, true. But thinking of it, it does hold a lot of merit. In the real world with those aircraft, if you need to "break", you get out of the sights of the one attacking you by pulling back on the stick with all your might while standing on one of the rudder pedals. Controls can get VERY heavy and that is basically the way to exert most force on the controls. Adding roll subtracts from your ability to pull hard.

Hence, the slipping turn of somebody ahead of you, as mentioned by @GrungyMonkey, I would say is absolutely plausible be a common sight, hence I do not really doubt his source mentioning those. But it is impossible that in that exact moment, the plane was creating "more lift". It is more that the pilot could pull harder and yank the plane in a tighter circle well inside the actual enveloppe, rather than expanding it.

I think this was another exercise about that there can be a great lot of context to first hand accounts and they must be dealt with a good sponnful of salt, not because they are necessarily wrong, but that we as reader can't imagine all teh actual context te writer faced.

I seem to remember however that Amerinan pilots would alledge the Japanese pilots to fly in very coordinated manner, which actually makes them an easier target, as their trajectory is more predictable. Given the best way for lead shots was centering on the bandit, pull the trigger and then just walk up the tracers on the other guy until he disappears under the nose. Rudder is the best way to escape then.

So yes, in this context, it all makes perfect sense.

[GrungyMonkey]

On 10/5/2023 at 10:31 AM, ZachariasX said:

If going sideways was a more benefical way for flight, every airliner would go sideways in level flight to save fuel.

In a "tight circle" you are at maximum lift. Any slip will do one thing: it will increase total drag and it will reduce total wing lift. Both effects expand and prolong your turning circle. If the air flows over the wing at an angle, the distance from root to trailing edge will be longer, hence the aerodynamic profile will be thinner, reducing max. lift coefficient. (That is also a reason why wing sweep is nice when going fast.) Frontal drag will increase with both the increase of frontal silhouette scaling by the square!) and by the reduced aerodynamic drag by having a lesser aerodynamic shape in the airflow.

The people you refer in that link to don't prove at all that side slipping increases total lift, they actually admit that they don't know and some of their musings are preposterous in context of a maximum turn maneuver. And to answer the question they raised, the lift and drag are changed when slipiing that with progressive sideslip, drag is increased and lift is decreased as well. You don't need CFD for that. That in case of dihedral, that the leading wing will have "more lift then the other" is certainly true, but in total it is a loss over any wing when flying straight. It is true that fuselages can produce a lot of lift (like in the F-15 or a Su-27), but those round fuselages like the one of the Zero don't do that for any practical purpose.

Slipping is a standard maneuver for a purpose. There is nothing mysterious about it. The side slip is a maneuver to steepen your approach. It acts as an airbrake. It steepens an aproach, because the aircraft performs progressively worse aerodynamically with a progressive increase of the side slip angle.

You should really close that book and never open it again. I'll leave it at that now.

It finally hit me what might have happened. Maybe the Oscar pilots were flying uncoordinated, and the 'sideslipping' they talk about from the Zeroes was actually them flying coordinated?

[ZachariasX]

On 11/29/2023 at 9:30 PM, GrungyMonkey said:

It finally hit me what might have happened. Maybe the Oscar pilots were flying uncoordinated, and the 'sideslipping' they talk about from the Zeroes was actually them flying coordinated?

Different poeple have different flying styles. I consider first hand anectotes highly circumstancial. Also, we (or I) do not know if that flying style was intentional or not. (I'd yaw to help me looking over my shoulder, I don't have an owl's neck...) Some of these fighter aircraft exhibit rather strong trim changes in yaw across the speed range that has to be comensated for by the pilot. In a tight turn, the aircraft bleeds speed a lot and gets out of trim unless the pilot insinctively does the right footwork (and this is really you pumping iron!), else the plane will progressively yaw during the turn.

It takes an experienced pilot to deal with such under difficult conditions. The IJN had extremely trained aircrew in te first year of the war and I am rather sure that those folks knew how to handle their aircraft. Yet with untrained ones, especially in a situation where the pilot is not looking over the nose (but much rather over his shoulder) to straighten out the aircraft, I find it plausible that the plane gets out of trim when the pilot is a lesser calibre.

Trim changes are really something prominent that differ these vintage aircraft from todays more balanced propositions. GBut going sideways puts very undesireable loads on an airframe form a design point of view, hence for "balanced" controls, the rudder is always kept with heavyer input loads than pitch or roll. The Mustang for instance got his tail fillet as it would yaw too easily. Yaw combined with pull loads changes the structural strenght on g loads negatively. This is a reason why you generally don't really flick roll vintage aircraft, unless they are rather slow and strong built ones (like an AT-6). But even with aerobatic trainers like a Bücker131 biplane, flick rolls are frowned upon, as these loads can stress and damage an airframe in a way that is not repairable, despite keeping nominal g loads well within limits.

[Lusekofte]

I have no records to show for. But really. The hard controls in high speed on the zeke is a no brainer in my eyes. It should be implemented. If you look at all pilot documentaries, animated or reenacted. The heavy controls at high speed is always implemented and in my eyes specified by the pilots the documentary is based on. 
 

[RossMarBow]

I think this is a good idea.
Removing the buff squidward from the pilots seat.

[GrungyMonkey]

3 hours ago, RossMarBow said:

I think this is a good idea.
Removing the buff squidward from the pilots seat.