S-3B Tanker - drop tank and buddy store contain no fuel (and are massless)

[Northstar98]

Hi everyone,

I've noticed that the maximum amount of fuel available for the S-3B tanker is the same as for the S-3B (non-tanker), at 12125 lbs (5500 kg).

This is despite the fact that the S-3B tanker in DCS, is always configured with a 300 US-gal drop tank (and of course the air refuelling store (Sargent-Fletcher A/A42R-1)).

The drop tank should obviously add 300 US-gallons of fuel and the buddy store itself also contains at least 300 US-gal of fuel (and the fuelling and dump port are present on the model). Right now, only the internal fuel of the S-3B is accounted for in the tanker unit.

 

They say a picture speaks a thousand words, so here's 3. Here's an image of the S-3B rearming window, showing a maximum of 12125 lbs of fuel:

 

Here's the same S-3B, but fitted with 2 300 US-gal drop tanks, note that the maximum amount of fuel has increased to 16155 lbs:

 

And finally, here's the S-3B tanker, which can be seen with a 300 US-gal drop tank and the A/A42R-1 air refuelling store, as you can see the maximum amount of fuel is 12155 lbs (as in the case with the S-3B with no drop tanks fitted):

 

Here's a source, approved for public release, stating that the D-704 pod has 300 US gallons of internal capacity (see page 2/page 8 of the pdf reader).

EDIT: As an addendum (thanks silverdevil) you can also see that the total mass of the aircraft for an S-3B with just internal fuel, is identical to that of the tanker - meaning that not only are the drop tank and air refuelling store empty of fuel, but are also massless.

Edited December 9, 2023 by Northstar98
spelling

[silverdevil]

41 minutes ago, Northstar98 said:

I've noticed that the maximum amount of fuel available for the S-3B tanker is the same as for the S-3B (non-tanker), at 12125 lbs (5500 kg).

hello. i have not looked myself, and this is probably just pedantics /semantics. the part in loadout circled is "internal fuel". now i also think that the total weight is changing with the addition of tanks, fuel, buddy tanks.

using my simple math each tank empty is 250 lbs. the fuel weighs 2000 +/- lbs. so two regular tanks weigh 4500 lbs. 43025-38775=4250 which is about right. but to corroborate you bug finding. screenshot three show shows no weight difference with empty loadout weight. screenshot two seems correct.

good catch.

Edited November 16, 2023 by silverdevil
spelling

[Northstar98]

On 11/16/2023 at 12:54 PM, silverdevil said:

hello. i have not looked myself, and this is probably just semantics. the part in loadout circled is "internal fuel".

AFAIK that only refers to the percentage slider, the fuel weight field should reflect the total amount of fuel (which explains why it increases when drop tanks are loaded, not just for the S-3B but every other aircraft that can be equiped with drop tanks) - how it's listed is somewhat confusing though.

It also explains why (with drop tanks equiped) you can set the percentage to 0, but still have a non-zero fuel weight (owing to the fuel in the drop tanks, which cannot be reduced or removed, unless an empty version of the tank is present). Of course without drop tanks (i.e internal fuel only), setting the percentage to 0, also results in 0 fuel weight, as expected.

Personally, it would be useful if the slider could switch between internal and total fuel where applicable, allowing us to alter the amount of fuel in the drop tanks (and make the separate empty versions redundant) or even more ideally, have the ability to specify the amount of fuel in each tank (including external tanks) while retaining the ability to set a total as we have now. This, though is probably something for the wishlist.

Good catch on the other weights though - as right now the tanks and air refuelling store not only contain no fuel, but are also massless.

Edited December 9, 2023 by Northstar98
spelling

[silverdevil]

2 minutes ago, Northstar98 said:

AFAIK that only refers to the percentage slider, the fuel weight field should reflect the total amount of fuel (which explains why it increases when drop tanks are loaded, not just for the S-3B but every other aircraft that can be equiped with drop tanks) - it is somewhat confusing though.

It also explains why (with drop tanks equiped) you can set the percentage to 0, but still have a non-zero fuel weight (owing to the fuel in the drop tanks, which cannot be reduced or removed, unless an empty version of the tank is present).

Good catch on the other weights though - as right now the tanks and air refueling store not only contain no fuel, but are also massless.

"internal fuel" is def a misnomer IMO. too much conflicting info in ME and within game for that to make sense. for example, if it is considered internal, then why does one have to go through nonsense to get drop tanks refilled on ground? i just dump them on the poor villagers prior to landing and just get new loadout.

[Northstar98]

On 11/16/2023 at 1:05 PM, silverdevil said:

"internal fuel" is def a misnomer IMO.

It's not really a misnomer, the percentage slider does only affect the internal fuel, but it would be better if the refuelling system was overhauled to make refuelling drop tanks easier (i.e have the ability for the slider to control either internal or total fuel (including drop tanks). That way in the rearming and refuelling window, you could set it to total and refuel everything (including drop tanks) or keep it to internal (and have it the way it is now).

Edited December 9, 2023 by Northstar98
spelling

[MAXsenna]

In any case. Does it have as much fuel as the previous version? If it's correct that's fine, it seems I can't fill as much as before, at least in the cRefuel Fight Recover" QS mission for the Tomcat.
Cheers!

Sent from my SM-A536B using Tapatalk

[Northstar98]

On 11/16/2023 at 1:53 PM, MAXsenna said:

In any case. Does it have as much fuel as the previous version? If it's correct that's fine, it seems I can't fill as much as before, at least in the cRefuel Fight Recover" QS mission for the Tomcat.
Cheers!

Sent from my SM-A536B using Tapatalk

Not sure as I (stupidly) didn't test, I guess down to reluctance to use it owing to the legacy model.

At a guess though, I wouldn't have expected this to have changed with the updated version as the update was just an artwork upgrade (there's still a few leftovers from the previous units, such as the names of the liveries (EDIT: not the case as of DCS 2.9.1), the names of stores and the types of stores available).

Though if you're experiencing that you can't tank as much, then that guess is probably unreliable.

In any case, the drop tank and air refuelling store shouldn't be massless and the S-3B tanker unit should have more fuel than just its internal tanks.

Edited December 9, 2023 by Northstar98
DCS 2.9.1 addendum

[MAXsenna]

Not sure as I (stupidly) didn't test, I guess down to reluctance to use it owing to the legacy model.
At a guess though, I wouldn't have expected this to have changed with the updated version as the update was just an artwork upgrade (there's still a few leftovers from the previous units, such as the names of the liveries, the names of stores and the types of stores available).
Though if you're experiencing that you can't tank as much, then that guess is probably unreliable.
In any case, the drop tank and air refueling store shouldn't be massless and the S-3B tanker unit should have more fuel than just its internal tanks.

Thanks! I'll guess I need to test it a little more!

Sent from my SM-A536B using Tapatalk

[Northstar98]

Looks like this issue was somewhat-ish addressed recently, though there's still some funny business going on:

The non-tanker version can now carry 13144 lbs/5962 kg of fuel internally, with a total aircraft mass (with no other stores) of 39793 lbs/18095 kg.

With a single drop tank those figures change to 15159 lbs/6876 kg and 41919 lbs/19014 kg respectively. With 2 drop tanks the figures are 17174 lbs/7790 kg and 44044 lbs/19978 kg respectively.

The tanker can now carry 15183 lbs/6887 kg of fuel at a total mass of 41833 lbs/18975 kg.

 

So, larger than just internal fuel, but the A/A42R-1 air refuelling store seems to only carry an extra 24 lbs/11 kg of fuel but somehow removes mass, compared the S-3B with a single drop tank. EDIT: Actually, this disparity in weight could just be the result of the ASW deconfiguration program, which removed much of the ASW equipment. Depending on the weight of the removed ASW equipment a post ASW deconfiguration program S-3B with a drop tank and refuelling store might weigh less than a pre-ASW deconfig. S-3B with a single drop tank. EDIT 2: Though it should probably carry more than just 24 lb of fuel in the air refuelling store - sorry Flappie

I'm not sure how much the A/A42R-1 weighs, nor how much fuel it carries; but the predecessor D-704 pod (with a very similar size and configuration) carries ~300 US gallons of fuel and weighs ~700 lbs (unsure if this is full or empty, though I'm leaning on empty as 300 US-gals of JP-5 is somewhere around 2050 lbs at 20°C) according to the source above.

Edited December 24, 2023 by Northstar98
Hopefully improved clarity

[silverdevil]

1 hour ago, Northstar98 said:

2050 lbs at 20°C

thanks for checking it out again. weird. the devs will eventually get it straight.

my cheeky response to your source. apparently the navy failed chemistry that year. Temperature does not affect mass. temperature does affect volume. /s

[Northstar98]

33 minutes ago, silverdevil said:

my cheeky response to your source. apparently the navy failed chemistry that year. Temperature does not affect mass. temperature does affect volume. /s

Nah, they (or rather cameochemicals) are good . The data sheet I used had a table of densities vs temperature - I simply picked one and worked out the mass from a given volume (300 US gallons).

Edited December 24, 2023 by Northstar98

[silverdevil]

23 minutes ago, Northstar98 said:

Nah, they (or rather cameochemicals) are good . The data sheet I used had a table of densities vs temperature - I simply picked one and worked out the mass from a given volume (300 US gallons).

 

[Flappie]

@Northstar98 I've not started to drink yet, still I'm not sure where we're at after reading your conversation.

Is it fixed, now?

[silverdevil]

2 hours ago, Flappie said:

@Northstar98 I've not started to drink yet, still I'm not sure where we're at after reading your conversation.

Is it fixed, now?

so i just looked. the s3b tanker is a bit heavier than the s3b. and the internal fuel is more. something odd was i could not create a loadout profile on the s3b tanker. ME only had "EMPTY". the picture in ME shows the D-704 on the starboard outer pylon.

[Northstar98]

On 12/24/2023 at 7:43 PM, Flappie said:

@Northstar98 I've not started to drink yet, still I'm not sure where we're at after reading your conversation.

Is it fixed, now?

Sorry!

The OP no longer applies but the main thing to be investigated is the total fuel, which still seems smaller than expected. I'm not sure how much fuel the A/A42R-1 air refuelling store adds but the previous D-704 (which is a similar size and configuration) contained 300 US gallons of JP-5, which translates to about around 2050 lbs, at 20°C; at the moment it currently carries 24 lbs.

The total weight of the aircraft is also less than the regular S-3B with a single full drop tank, that could be explained by the removal of ASW equipment seen in the tanker version in DCS, but it might be worth investigating.

 

Merry Christmas!

Edited December 29, 2023 by Northstar98
Expanded

[Flappie]

Thank you. Merry Christmas!