Bomb loads

[hubbabubba]

Too bad so many links have gone AWOL...

Good thing I decided to make my "Fun with SCASM" in HTML zipped format. The guy who wrote "Les paroles s'envolent mais les écrits restent." was obviously living long before WWW.

 

[Ivan]

Fun Flying with the B-25 Mitchell

Hello Hubbabubba, et al.

In this thread, we have gone through a pretty exhaustive discussion about what the appropriate standard size of a bomb should be for a CFS aeroplane in general and also what the appropriate bomb loads should be for various aircraft.

Hubbabubba has also given us pretty detailed coverage of bomb technology and practices which make for good academic discussion but also serve to remind us how rudimentary and primitive the "Bomb" has been handled in Combat Flight Simulator.

While the question of appropriate loadouts will always be debatable, there is another aspect of CFS bombing that has always bothered me: Attacking a Target.

With a small bomber such as a SBD Dauntless or Ju-87 Stuka carrying just one bomb, the technique is pretty simple:
Fly a path over the target.
At the appropriate time, press the bomb trigger (4) to release the single bomb.
Fly away.

The technique doesn't change much when there are 2 or 3 bombs being carried.
Just tap the bomb trigger (4) as many times as needed when over the target.
.......
NOW consider what happens when flying a larger bomber carrying many more bombs.
Imagine flying over the target in a B-29 with 40 x 500 pounders.
Is it reasonable to expect the Pilot / Bombardier to press the bomb trigger 40 times and distribute her bomb load over two or three counties?

I believe not.
Ideally there should be a means of dropping ALL the bombs quickly as a salvo.

The recent "Fun Flying" with a B-25 Mitchell was also intended to test different ideas to see if this could be done in CFS.
The B-25C is a fairly typical Medium Bomber. I decided that the version I built should be capable of carrying up to 5,000 pounds of bombs or 10 x 500 pound "bullets". (Default Bomb Load will be a subject for later discussion.)
Over a dozen flights were made (not including crashes) to test different configurations of DP file in attempts to determine the best way to allow the entire bomb load to be salvoed quickly.

The Standard Configuration
There is a single GunStation which has a single Gun which has 10 Bullets

The behaviour of this configuration is pretty well known. Each Trigger press releases a single bomb.


Multiple Guns
There is a single GunStation which has 10 Guns which each have 1 Bullet

I found it was actually impossible to implement this configuration. At most 8 Guns could be configured.
When using this configuration, it proved to only be possible to drop ONE bomb. The remaining 7 bombs would still show in the HUD and did not respond.


Multiple GunStations
There are 10 GunStations which each have a single Gun which each have a single Bullet

Each Trigger press dropped ONE Bomb. Repeated presses also dropped a single bomb. This result surprised me. One would have expected multiple gun positions responding to the same trigger to all fire at the same time but apparently the rules for Bombs are not the same as for other types of armament.

Thus ended the first series of flights which proved to be a bit less fun than expected.

.......

(More to Follow.)

 

[Ivan]

Further Testing with the Mitchell

After achieving no success with the DP modifications, I started thinking:
Combat Flight Simulator has been out for two decades.
Others certainly have found the handling of bomb loads to be a problem and if it were so easy to resolve, someone else probably would already have found a solution.

I didn't think remapping to one of the other Weapon Triggers was likely to work.
Other than the Gun and Cannon Triggers, the other Triggers appear to be very specific, non-controllable features.
In looking over Settings for possibilities for reassignments, I noticed that although Gun and Cannon were set to auto repeat, Rockets and Bombs were not.

I changed the Settings for the Bomb Trigger to auto repeat and found that with the exception of multiple Guns in a single GunStation, I could drop the entire bomb load very quickly by just holding down the Bomb Trigger!
The sound was of two bomb releases.

The INTERESTING Thing was that the bomb impact craters seemed for form a different pattern with different configurations of the DP File.
I decided to make a quantifiable comparison of impacts by making each bomb run from 2000 feet.
Here are the results:

(The B-25 Mitchell is flown over the Bomb Craters at 100 feet for a relative size comparison)

The First Screenshot shows:
1 GunStation, 1 Gun, 10 Bombs per Gun - The Default Configuration

The Second Screenshot shows:
1 GunStation, 10 Guns, 1 Bomb per Gun - Note that there is only ONE impact crater

The Third Screenshot shows:
10 GunStations, 1 Gun, 1 Bomb per Gun - Compare the distance between first and last impact

.......

 

[Ivan]

Bomb Runs Repeated

Bomb runs were repeated with very similar results.

Just out of curiosity, I wondered what would happen in an extreme case with MANY bombs.
The Mitchell's bomb load was replaced with 100 x 50 pound bombs and the bomb run was repeated.
Attached are two screenshots of those bomb craters.

The First Screenshot is with the B-25 at 100 feet altitude but the entire length of the craters cannot be seen from this altitude.

The Second Screenshot is with the B-25 at a much greater altitude.

These tests show that the combination of GunStations and Bombs can determine the length of the bomb pattern that is dropped in a salvo from an aircraft.

From these tests, I know how I will configure the DP in my B-25C.
Hopefully these tests can give other people ideas that can be used in developing new projects.

- Ivan.

 

[Ivan]

Maximum Take-Off Weights

The B-25 Mitchell in most of its versions had a maximum Take-Off Weight of 33,500 pounds.

The Zero Fuel Weight of the MitchellC is 22,750 pounds.

The Disposable Loads are as follows:
The typical B-25C carried either 5 or 6 x .50 cal Browning HMG.
Two were in a Dorsal Turret
Two were in a Ventral Turret
One was a flexible mount in the Nose.
Some aircraft carried an additional fixed .50 cal that could be fired by the pilot.

The DP file gives each gun a 1000 round ammunition load so the total ammunition is either 5000 or 6000 rounds.
.50 cal ammunition early in the war was 5 ounces per round (later it became 4.8 ounces) so MG ammunition would weigh

1562.5 pounds
or
1875 pounds

Fuel was carried in a Main and Auxiliary Tank in each wing.
Main Tanks - 184 Gallons each
Aux Tanks - 151 Gallons each
Total Fuel - 670 Gallons == 4020 pounds

The DP file allows for a maximum bomb load of 5000 pounds.
In reality, the Mitchell could carry additional loads externally, but that is not accounted for in the DP.
(A 2000 pound Torpedo could be carried externally.)

As configured for CFS, the MitchellC with full bomb load would have a loaded weight of either
33,332.5 pounds with ammunition for 5 MG
or
33,645 pounds with ammunition for 6 MG.

It seems like the pilot may need to make some choices if he wants to stay at or below the Maximum Take-Off Weight.

- Ivan.