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An introduction to the M47 in Korps Mariniers service

The Amphibious Combat Group (AGGP) possessed a single anti-tank platoon (atpel) in its weapons company (ostcie)

Original document, translated

a. To investigate the weapon system’s behaviour in arctic environments;
b. To investigate possible interference to the weapon system;
c. To investigate the influence of interferences on the guidability of the wire-guided rocket;
d. To gather information which concerns the tactical use of the weapon system.

A trial schedule was created to investigate a number of phenomena. This was done under informal cooperation with the Materieelsbeproevingsafdeling – 1, located in Zaandam.

a. Rounds were fired by gunners who had qualified “0068” or “0069” in the past 3 to 8 months, all of whom had already fired the M223 rocket at the ISK Harskamp.
b. All rounds were fired at a stationary target from lanes 13 and 14 at the Drevja range, Norway. The target consisted of a wooden frame covered in burlap, measuring 3 metres wide and 1.8 metres high. Firing took place at distances of 700 (lane 14) and 800 (lane 13) metres respectively.
c. Before firing the weapon system, the launch units were laid out in the snow for several hours. The trackers were continuously stored in unheated spaces for the duration of the trial, and were inspected both during and after trials using a tracker sight testing unit.
d. Every shot fired was captured by a technical photographer of the Marine Electronisch en Optisch Bedrijf, Wassenaar.
e. Every shot fired was evaluated by means of an interview during which all observations and results were recorded in a trial report. An example of the used form is included in the appendix.
f. Of the 42 launch units trialled, only 26 rounds were fired during the final phase of trials as a result of relatively high outdoor temperatures (±0). This creates a certain bias with regards to the reliability of conclusions that can be made based on the firing results and observations.
g. The 42 packed launcher units were stored in an unheated bunker in Drevja for a duration of 3 to 4½ weeks. Upon inspection of the launch units, the moisture indicators on the forward shock absorber were discoloured to “ROSE 30”, meaning the weapon can be fired but must be stored in a different manner (see VS 7-611 Koninklijke Landmacht and Zakboek voor de schutter Korps Mariniers p. 14). As a result of continuously changing weather and temperature conditions during the trial period, the number of thermal shocks (transitions warm-cold/cold-warm) could not be accurately determined.

a. No interference or defects to the used tracker sights were noted. Breathing on the ocular must however be avoided.
b. Of the 26 rounds fired, 14 would hit compared to 12 misses. An overview of hits/misses and meteorological circumstances can be found on the following page.

c. During trials, the following phenomena were noted:

1. Excessive flash

Excessive flash was noted sixteen times upon the activation of the propelling charge and after the launching of the rocket from the launch tube. The following processes took place inside the launch tube (for a maximum of 2 seconds):
- Activation of the propelling charge and expulsion of the rocket
- Vacuum phase
- The formation of flashes from the rear to the front (“leakage”).
The above-mentioned “leakage” flashes form as a result of the propelling charge’s powder particles afterburning inside the launch tube, and last for 1 to 2 seconds. The target’s visibility is influenced by these flashes, causing the gunner to see a yellow haze through his sight. It could not be established as to whether the “leakage” flashes influenced the infra-red mechanism present on the sight.

2. Excessive smoke

Due to the rearward flow of the propellant charge’s gasses, a plume of smoke has been noted behind the firing position 22 times. This white-grey plume of smoke was visible between 3 to 24 seconds.

3. Uncontrolled flight

Seven times, the rocket’s flight was uncontrolled. During one occurrence, the rocket thrusters were not activated after activation of the propelling charge and expulsion of the rocket from the launch tube. Upon further inspection of the guidance wire and the rocket, it was found the guidance wire was intact. The 60 rocket thrusters were still sealed.
In another single instance, the guidance wire broke (see point 4).
During one occurrence, it was suspected the gyroscopic mechanism had jammed. The rocket followed an upward trajectory, during which the rocket thrusters only gave off upward corrections. The rocket travelled a distance of 1400m. Such a flight path has been previously observed during trials by MBA-1.
Four instances have been noted where the rocket barely or did not respond to the gunner’s corrections.

4. Broken guidance wire

In one instance, the guidance wire broke off. The wire had broken inside the launch tube (30 cm of wire remaining), with the other section of wire (1050 metres) still attached to the rocket.

5. Wire pulling

Nine instances were noted where the rocket pulled on the launch tube during its flight. Instead of the wire unspooling in an even manner, the rocket would impose pulling and shocking motions upon the launch tube after having travelled 600 metres.

6. Delayed response from the rocket

It was noted five times how the rocket would respond to corrections with a delay. The rocket would (at both short and long range) swerve to the left and right of the line of sight. This caused the flight path and the line of sight to misalign during the final part of the flight path, causing three misses. Two hits were however noted, presumably due to the target and the rocket’s swerving motion aligning. The delayed response was only noted during the first day of firing (average temperature, - 14 °C).

a. During trials of the M47 Dragon weapon system, rocket type M223 it was shown the weapon behaves differently from trials in the Netherlands. Phenomena not previously noted were: excessive smoke and flash, wire pulling, delayed responses of the rocket.
b. Launches and flight path were not without issue. A number of the issues have also been noted in the Netherlands: broken guidance wires and jammed gyro mechanisms.
c. The influence of the pre-trial treatment of the Dragon does not appear to significantly influence hit probability. The number of thermal shocks could not be determined, the height at which the launch units were dropped was 75 cm (surface: frozen snow), the launch units were horizontally stored in the BV 202 in their racks.
d. The negative effect of being stored in moist conditions can not be ruled out with regards to the launch units’ functioning.
e. The issues and noted phenomena during the launch and flight of the rocket influence the system’s hit probability. The hit probability at temperatures below freezing (down to – 32 °C) could be lower than previously suspected.
f. Phenomena such as excessive smoke and flash could be of influence for the tactical use of Dragon-equipped anti-tank units. The firing position may possibly be easily recognized.

a. In light of the experience gathered with the M47 Dragon M223 in Norway, the conditions under which Dragon launch units M222 (especially war stocks) and M223 are stored in the Netherlands must be examined.
b. As the trials were incomplete, it is recommended further trials are undertaken during Clockwork 1983 in Norway, testing the Dragon’s behaviour at temperatures between -15 °C and - 32 °C.

Annex 1

a. After firing

(1) Formation of fog: yes/no
(2) Target visibility: good/mediocre/poor
(3) Target visible after: ... sec
(4) Target visible after: ... metres
(5) Notes:

b. During the rocket’s flight:

(1) Formation of fog: yes/no
(2) Target visibility: good/mediocre/poor
(3) Rocket’s controllability: good/mediocre/uncontrollable
(4) Notes:

a. Position : ... metres to the left/right of the firing position
b. Formation of fog in proximity of the firing position: none/all around/sides/front/rear
c. Duration of fog: ... sec
d. Snow cloud in proximity of the firing position: none/all around/sides/front/rear
e. Duration of snow cloud: ... sec
f. Further comments:

a. Position : ... metres to the left/right of the firing position
b. Formation of fog due to thrusters: yes/no
c. Duration of fog: ... sec
d. Firing position identifiable as a result of fog: yes/no
e. Further comments:

The Clockwork '82 Trials: summary and conclusion

Original document