N1K2 Flaps

[Charge]

The schematic does not make sense to me.

1. There is no apparent connection between electrical and hydraulic part.
2. If the lever L3 goes down valve V2 opens "down" and  the flaps are opened by pressure in l3 but at the same time V1 is also forced open "down" too by L3 and V1 tries to push the flaps closed via l4.

Only thing logical seems to be that all the G that affects M1 and M2 aims to prevent the operation of flaps.

Also the operation of S1 is weird.

 

-C+

[2bighorn]

I'm well past the hardware portion of my career as well but the pitot signaling is only going to be good for determining speed, be it based on dynamic, statis, or differential pressure. I'm thinking the one on the right looks more like a something that uses a lateral g signal.

It is both, G and speed dependent.

[nrshida]

That's genius. A self adjusting analogue system reacting to both airspeed and G-force. Thanks for posting that WMaker.

[nrshida]

Wonder what the fifth hydraulic jack is for (on the bottom right of the page).

[Rolex]

It's not a hydraulic jack. The diagram says its an arm that switches between high and low speed flap operation.

[nrshida]

I'm not sure we are talking about the same component Rolex. Beneath the four jacks that actuate the flaps there is a fifth hydraulic jack with it's own feed and return, do you mean this jack actuates a valve in the hydraulic system to change the speed of the other jacks?

[Wmaker]

Thanks for the translation Rolex!

Here's what is being said on the upper part of the same page which those scematics are from:


Electrical/hydraulic scematics of the whole plane:


Positioning of the hydraulic components:

[Rolex]

Sorry, but there is a page previous to this one that starts the explanation of how the system works. We're looking at the middle of it, not the beginning.

I don't have time to translate and analyze all the diagram components right now (give me some time), but the text says:

The pilot uses his left hand to work weapons levers and his right hand to fly. His feet are on the pedals. Once he's tracking one or several bandits in combat, setting optimum (Fowler) flaps is near impossible to do efficiently. There is a button to control extension and retraction of flaps under normal flying conditions.

In combat though, the pilot is so busy, it's not humanly possible to set optimum flaps for a particular g loading and airspeed condition. Could it be done automatically? That is what the designers set out to do. A pilot under high g loading in turns couldn't reach and set flaps, so they created an automatic system to extend and retract them based on g loading and airspeed.

I'm sorry I don't have time to give a more complete translation of the new schematics posted. Later...

Note to Krusty: There is no mention that this system was developed to compensate for poorly skilled pilots.

nrshida: it's a lever or arm and not another hydraulic jack (they are pistons). The hydraulic system has two speeds or pressures and the pilot selects high speed or low speed hydraulics. High is for landing gear operation and low is for flaps operation. The pilot has to select high speed to extend gear, then back to low speed after gear is down and locked to operate flaps, and vice-versa for gear retraction.

[nrshida]

I understand, thank you for your explanation. A very clever and elegantly simple solution. Fascinating to see the engineering solution with the available technology of the day.

So has the case been successfully made for the request to add automatic combat flaps the Aces High's N1K?

[Rolex]

I'm not satisfied that I understand the complete operation or mechanism of the system yet. I would need to see more pages of the book with all the text. Some of the text is clipped.

I was wrong about there being two flap speeds until I had the text to explain there was a selector between flaps and gear operation within the unified hydraulic system. Apparently gear and flaps cannot be operated independently. I'd like to see more text describing the automatic flap mechanism.

I'm not a translator by trade, so please bear with me as I try to help.

[busa]

Hello.
This is busa01.

Since I am making the skin now, I cannot use much time about this affair.
(The skin of A6M3 Model32 was submitted last month) .
And the work of A6M5 and M2 is continued.

By the way, I have Pilot Hand book and the manual of N1K.
Translation of Pilot Hand book has been performed mostly.
I make an extract and introduce about how to use Automatic Combat Flap later.
I have to explain a control system before it.
It will be difficult for me to explain it by translation software.
Although it may go wrong, I will challenge.

I write ACF [ Automatic Combat Flap ] after this.

I want you to think first that this system is equipment which raises a flap.
Probably I think that it can understand ACF easily.
By the way, the sketch of the control unit of ACF has two faults.
I think that this sketch is very unkind.
And the two points are the maximum important parts of an ACF controller.
Notes are following two.
No.1  This electrodes of different length is interlocked with a flap angle.
No.2  The height of a mercurial column does not specify what is shown.

I give explanation which contains notes No.1 first.
About the state when gravity is 1G
When speed is 0.
In an initial setup of this equipment, the flap becomes a full down. Therefore, the cam shaft is rotated to maximum. The electrodes is set to the lowest position.
But since there is no dynamic pressure, two electrodes do not contact mercury. In my memory, the electric system at this time sends a flap lowering signal.
Similarly by my memory, the oil pressure system is protected by the bypass circuit at this time.
I am sorry,I am not checking these two points this time.
 
Then, I will increase the speed of N1K.
 Incidentally the stall speed of N1K2-J is the following.
 71kt No flap weight 3900kg(about fuel 80%)
 66kt 30deg flap wight 3900kg(about fuel 80%)
 Normal fighter full road (full of fuel No DT) is 4000kg.
When the speed of N1K passed over stall speed and set to 73kt.
By increased dynamic pressure, a mercurial column becomes high and contacts electrodes of the shorter one. The electric system sends the signal which raises a flap. Flap goes up, a cam shaft rotates and electrodes also goes up.

When it becomes constant speed.
The electrodes goes up and only the longer one will be in the state of contacting mercury. The electric system suspends the operation of a flap.

Furthermore, I will increase the speed of N1K.
A mercurial column becomes high by increased dynamic pressure. Flap goes up, a cam shaft rotates and electrodes also goes up. It continues to 106kt and a flap angle is set to 0 after it.

To be continues.

[PJ_Godzilla]

I understand, thank you for your explanation. A very clever and elegantly simple solution. Fascinating to see the engineering solution with the available technology of the day.

So has the case been successfully made for the request to add automatic combat flaps the Aces High's N1K?

I think the case to add it has been made, depending on the criteria for inclusion. IF inclusion requires that the system existed and was used, then I'd say we're airtight. OTOH, I do not know the criteria, so my point could be moot.

Additionally, even if we can say that the case to add is made, the "how" of it is still open - i.e., I think what we'd really need is a 3d surface showing flap deployment versus speed and lateral load, if, as Rolex asserts, the system is both speed and lateral-g dependent (and this makes intuitive sense).

Also, thanks for the explanation, Busa - the system appears to control flap retraction. My wife will be gratified that I'm not bugging her to translate anything (yet).

[busa]

Then, the case when G increases this time is explained.
Supposing I have succeeded in explanation of the operation in 1G, this may not have necessity.

When G increased and the mercurial column of manometer lower.
Both of electrodes un-contact a mercurial column.
The electric system sends the signal of flap lowering.
Flap lower and electrodes of the longer one contacts a mercurial column.
Then, an electric system suspends the operation of a flap.
When G decreases, short electrodes contacts mercury and a flap goes up.
When dynamic pressure increases, a flap goes up similarly.

That is, the optimal flap angle is decided by the cam shaft.
To what is the optimal?
Probably, about it, everybody knows well.
Coefficient of Lift=nW/SPd.
About variable n/Pd of this formula
In the early stages of development, Kawanishi Avi tended to measure n(G) by G sensor.
The dynamic pressure tended to measure by the diaphragm.

However, it has been noticed that the height of the mercurial column of manometer is h=Pd/n(G).
The ACF controller was able to be made to small measurement by this suggestion.
And it became hardly breaks down.

By the way,When speed is incidentally 250kt or more, a restriction circuit operates by the diaphragm.
And in inverted flight, a flap goes up by inverted flight electrodes.

Did I succeed in translation? .

An intelligible sketch.
cAircombatFlap.jpg" class="bbc_link" target="_blank">http://ja.wikipedia.org/wiki/%E3%83%95%E3%82%A1%E3%82%A4%E3%83%AB:Manometerunit_of_the_Automati cAircombatFlap.jpg

You can see the original data to the following sites.
http://www.jacar.go.jp/english/index.html
N1K2-J prototype plane Manual.
A03032263000
About reference data
N1K1 Rex 2 stage Combat flap test report.
A03032133000
In addition, Pilot hand book and production plane Manual are not processed electronically.

How to use ACF is written in later again.

Thank you.

[Wmaker]

Thank you so much Rolex and Busa!

Sorry for my late reply!

Rolex, here's the page where that chapter starts. There were pages with full of pictures before that last part so I assumed that was all there is to it. Hard when you can't read a single writing symbol...



(Sorry for the poor scan which leaves text out from the bottom, this is all I have I'm afraid. )

[Ack-Ack]

Note to Krusty: There is no mention that this system was developed to compensate for poorly skilled pilots.

Everything from what I've read about the flaps on the N1K2 was that they were designed to aid the pilot, not so much to compensate for any lack of skill but rather to keep the pilot from having to do an additional task while in combat. 


ack-ack