Two Historical Firing Methods: Ausdampfverfahren and Auswanderungsverfahren

[derstosstrupp]

Hi All,
Introducing two firing/data acquisition methods which, after repeated tests using the torpedo tutorial in the academy, have proven to be successful and are 100% historically accurate, which ought to make other fellow “targeting realism” die-hards grin. I am using NYGM with Hitman’s GUI.
These methods are:

1. Ausdampfverfahren - (constant bearing to target)
a. Advantages/Requirements:
i. requires no estimate of target AOB or speed prior to firing
ii. requires only maintaining a constant bearing (collision course) and knowledge of own speed
iii. requires range estimate to correct for parallax prior to shot, but can be roughly estimated
iv. can use to derive target speed with solid knowledge of AOB
b. Disadvantages:
i. not optimal when target AOB is small when on collision course due to small target presented for the torpedo
ii. less accurate than plotting during the overhaul maneuver, and is thus best used when encountering the target forward of the beam (say at 45 deg AOB or so)
iii. should not be used for night surface attacks, as Hundekurve (dog’s course, keeping bow to target) should be followed to minimize sub silhouette.

2. Auswanderungsverfahren - (change in bearing of target over 1 minute)
a. Advantages/Requirements:
i. requires no estimate of target AOB or speed prior to firing
ii. requires one rough range estimate, own speed, and the bearing change of target over 1 minute
iii. requires final range estimate to correct for parallax prior to shot, but can be roughly estimated
iv. can be used at long distances during the overhaul maneuver to obtain rough speed with a rough idea of target AOB without slowing and thus losing time in overhauling
v. can be used to derive actual target speed with solid knowledge of AOB
vi. allows more freedom of maneuver than Ausdampfverfahren as no requirement to keep a constant target bearing, and thus can be used for night surface attacks
b. Disadvantages:
i. Less accurate than the Ausdampfverfahren and plotting during the overhaul maneuver, and is thus best used when encountering the target forward of the beam (say at 45 deg AOB or so)
ii. not optimal when target AOB is small due to small target presented for the torpedo and need for appreciable bearing change

Of course, the results of either method are only valid if the target maintains course and speed. For both methods, a scientific calculator with trig functions (otherwise known as your WO standing near you working the slide rules) is also necessary.

I will preface this by saying that by no means are these original ideas; these methods are historical and come from the Torpedo-Schießvorschrift (torpedo firing provisions) from 1930. I credit my knowledge of these methods to the gentleman who put together this site:

http://www.tvre.org/en/acquiring-torpedo-firing-data

This site outlines the ins and outs of the real-life Torpedo-Vorhaltrechner (German TDC) as well as other ancillary information and is a must-read for all who haven’t yet. The page linked above details the methods of acquiring firing data and includes the methods I will be demonstrating below. Thus, I am merely compiling these methods below in a thread for ease of reference and implementation into SH3.

I will discuss each method in a separate post to follow.