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[mizusummer]

D4Y2 can not take off from CVshokaku with 500kg bomb
By reducing the fuel to 60%, it could barely take off.

I don't know if this is a spec in the BAT or a bug, but I think the power is too low.

I am very disappointed to see the D4Y2 which cannot take off from a carrier even though it is a carrierbased bomber.

[taly01]

D4Y has not great takeoff,  it was not used on Japanese small carriers IRL.
Can AI takeoff with it?
Is the carrier travelling into wind?
Was the 500kg ever actually used off carrier?  Mostly was 250kg??
For player is power maxed, chocks in for take off, and correct flap setting.
Some up trim also helps.

[glibble]

Mizu's right, the plane is severely under powered in the game.
While historically the liquid-cooled engine did give IJN trouble, it couldn't be THAT slow.

I tried 1x250kg bomb, 100% fuel, CV Shokaku going full speed, and my plane crashed into the sea.
This is probably the most standard takeoff scenario that IJN would have asked for.

I had to reduce fuel to 80% to barely takeoff, but my AI buddy didn't make it

And Shokaku is not a small carrier, it is standard sized.

[Yaro59]

[Wing Walker]

I tested this out just because it is interesting to try when people post these "problems"...

IRL planes could not just launch from carriers carrying any fuel load and payload they wanted, especially if there was no catapult...

The D4Y2 here WILL launch from a carrier in BAT with AI flying them.

So first I went with the fastest Jap CV speed in WW2 which was 61Kmh, so I set the no cat Jap carrier to 65kmh since they never stay at the kmh you set.

There is a weight limit for the engine power.

You can't take off weighing more than 9542Lbs with the CV going 61kmh.  If you are at 9542 it will take off just skimming the water before it starts to climb, a real person can probably do a little better, if you weigh less than that it works better.

This 9542 Lbs goes for any fuel/ordinance combination you have.

Here are the weight fuel combinations that let the D4Y2 to take off from a CV (non-catapult) going 61kmh (set to 65kmh) lower fuel by 5-10% for easier takeoff:

Default + 90% fuel (9542Lbs)

250kg Bomb + 70% fuel

500kg Bomb + 55% fuel

 


Yaro59
That video is not helpful because it does not show the weight of payload/fuel, nor the speed of the carrier.

[Dimlee]

I have a temporary pause with BAT, so I tried Ultrapack.

IJN Carrier Generic, full speed 63 km/h.
No wind.
D4Y2, 1944.
100% fuel, 500 kg bomb.
No catapult.
She takes off fine and leaves the deck at about 160 km/h.
Overall, D4Y2 is surprisingly agile and fast climbing with this loadout. I have no idea if this is "historical" or not.

[glibble]

I'm amazed at how fast Yaro was able to upload that video!

@Wing Walker,
I followed your advice and did a few tests.
A few observations:

1. The test I did in my earlier post was with Shokaku CV going 63kmh, and my fuel tank was 80%, with 250kg bomb. The total weight would have been 9730Lbs. And like you said, it exceeded the 9542Lbs limit and crashed.

2. Yaro's video showed Akagi CV as example. Akagi's flight deck is significantly higher than Shokaku's, which probably gives the pilot more room to pull up during takeoff. I tried the same 80% fuel + 250kg bomb combo on the Akagi, and IT WORKED, even for the AI. Too bad the real Akagi wasn't around when D4Ys went into full service.

3. Somehow D4Y's predecessor, the D3A1, is able to take off with 100% fuel + 250kg bomb under the same circumstances WITH EASE. A bit inconsistent don't you think?

@Dimlee
Somehow I think the D4Y2 in your Ultrapack is on steroids
I'm on BAT 3.6 and I don't even have the 500kg bomb option.
The D4Y3 in BAT, however, is a lot more powerful than D4Y2.

Anyway, just some thoughts.

[Wing Walker]

3. Somehow D4Y's predecessor, the D3A1, is able to take off with 100% fuel + 250kg bomb under the same circumstances WITH EASE. A bit inconsistent don't you think?

Its hard to say without looking up the real life performance of these aircraft.  The Val may have had a better engine, or more wing area for lift in real life.

Though in BAT the D3A1 weighs in at 7837 Lbs, that is 1705 Lbs lighter than the D4Y2 with a Default loadout...

If you could put the D4Y2 in BAT down to that weight it would take off with ease also...

Testing @ 5000m flying for 5mins:

D3A1
100% Fuel + 250Kg bomb (no 500kg)
SPEED = 243kmh

D4Y2
100% Fuel + 500Kg bomb
SPEED = 280kmh

So the D4Y2 seems to have slower acceleration, or wing lift, but can carry a heavier pay load and fly faster at the same time than the Val.  Just is limited when taking off from a Carrier.

The F4U Corsair was able to fly carrying a payload of 4,000Lbs (1 2000Lbs and 2 1000Lbs bombs) but it could only do that from a land base with other very special perimeters.

 

[mizusummer]

Thank you all for your replies. My sincere thanks to those who verified it.

ShokakuClassCV is a representative carrier that actually operated the D4Y2, and its size can be said to be standard for the IJN, and even the smaller and slower Junyo is equipped with it, albeit in smaller numbers, so there should be no problem with Shokaku!
However, the D4Y2's weight and fast landing speed made it difficult for the IJN's CVLs to operate in the late WW2 era, when the IJN lost its larger aircraft carriers.
For these reasons, I have tried to use Shokaku to take off the D4Y2.

Interestingly, as Dimlee commented, I also remember that with DBW, even with a full load of fuel and 500kg of bombs, I was able to successfully take off.
Unfortunately, DBW is no longer activated, so I don't know if it is possible now.

Again, thanks for your reply and verification. You've made me feel much better.

[glibble]

Just did a quick search for "D4Y" on this forum and looks like many users have complained about it's lack of power before 

Vasya posted a link to a new FM before (Reply #138):
https://www.sas1946.com/main/index.php/topic,23904.132.html

Did anyone try it?

[taly01]

The BAT games coded propeller setting for D4Y may need a little tweaking, more low speed pitch and propeller thrust speed setting a bit lower.   Original il2-Pacific Fighters cheated by giving all carrier planes perfect thrust from 0kph.  Carrier take offs should be exciting but not 50:50 chance.   
I have only seen mention of 250kg dive bomb for D4Y, but would like to see if 500kg dive bomb was really used. 
I think the D4Y had a high speed wing unlike the sail on the D3A, also the weight difference noted in above posts not helping either.

 

[Whiskey_Sierra_972]

Just did a quick search for "D4Y" on this forum and looks like many users have complained about it's lack of power before 

Vasya posted a link to a new FM before (Reply #138):
https://www.sas1946.com/main/index.php/topic,23904.132.html

Did anyone try it?

Hi!

Just tested....

Now it could take off with full load (2 x 300 dt or 1 x 500 bomb) and 100% fuel even if it go down to 8 mt (25ft) asl with AI set at ace from the Shokaku travelling at 65kmph....maybe human should reduce a bit the fuel to the level needed for the mission length....

Tesed also the other 2 proposed version included in Vasya pack , the D4Y4 and D4Y5....not installed because they use the inline engine and need Vasya weapons mod and atm I prefere to avoid working on WAW before I have to do it in the future of my updates....

The real one should have used the radial (but it could be an easy fix , only change the 3d) and for weapons need only find the correct weapons to be added to avoid possible conflicts between BAT and Vasya....