Armored Medical Research Laboratory Fort Knox, Kentucky First Partial Report On PROJECT NO. 24 - STUDY OF HEAD PROTECTION FOR TANK CREWS Project No. 2U 13 June 194 5 ARMORED MEDICAL RESEARCH LABORATORY Fort Knox, Kentucky SPMEA 727-121 Project No. 24 13 June 1945 1, PROJECT: No. 24 - Study of Head Protection for Tank Crews, First Partial Report. a. Authority; 9th Ind. 421.2(H), 12 Nov 43, GNRQT-6/69160, 1st Ind. OQUG-389, 15 Jan 43. b, Purpose: To summarize development of helmets for tank crew members with particular reference to Quartenn&ster liner now being considered for adoption, 2. DISCUSSION; a. A meeting was held at Armored Medical Research Laboratory, 6 May 1944# to consider a helmet to replace Ml helmet and liner and football-type helmet for tank crews1 use. Members of AGF, OQMG, The Armored School, Armored Board and AMHL were present. It was decided that two lines of development should be followed: (1) Primary design of crash helmet with superimposed steel helmet, (2) Ballistic and crash protection combined in one unit. The Quartermaster liner now being considered is the result of development (1) above. Ordnance is preparing samples of steel helmet to fit over the Quartermaster liner. Ordnance is also preparing samples of combined helmet in accordance with development (2) above. Field tests have been run on the Quartermaster helmet and will be run on Ordnance helmets as soon as avail- able, Inasmuch as the basic considerations for tank helmets are the same whether with integral or separate armor, the design problems will be considered together in Appendix A. 3o CONCLUSIONS; a. The latest version of the Quartermaster tank helmet is considered satisfactory for crash protection provided the chin strap support is moved from the outside to the inside of the helmet. b. The Ml steel helmet may be worn with the Quartermaster tank helmet by personnel outside the tank or when traveling with hatches open but is not satisfactory for use inside the tank, c. Where armor protection inside the tank is required, a modified steel helmet to fit over the Quartermaster helmet or a unit steel helmet with suspension equal to the Quartermaster helmet will be required. Both of these type helmets are now in development by Ordnance, d. The modified head rest recommended in AMRL Project No. 6-1, 6-2, 6-3, 6-4, 6-6 - Vision in Tanks — Eye Cups, Head Rests, and Head Clearances, dated 6 September 1944, is required for periscopes and mounted spotting binoculars to be used by personnel wearing the Quartermaster tank helmet or Armored versions under development by Ordnance, 4. RECOMMENDATIONS: a. That with the change in chin strap support from outside to inside, the latest version of the Quartermaster tank helmet be considered satisfactory for crash protection for tank crew use, b. That standard Ml steel helmet worn over Quartermaster tank helmet be considered satisfactory only when worn outside the tank or with head out of open hatches and not satisfactory for use inside the tank, c. That headrests of the type recommended in AMRL Project No. 6-1, 6-2, 6-3, 6-4, 6-6 - Vision in Tanks — Eye Cups, Head Rests, and Head Clearances, dated 6 September 1944, be procured and installed on periscopes in tanks for use with the Quartermaster tank helmet. d. That Ordnance development of Armored steel helmet to fit over Quarter- master tank helmet be continued to provide armor protection which will be satisfactory for use inside the tank in addition to use with head outside open hatches or outside tank, e. That present Ordnance development of one piece steel helmet be completed for comparative evaluation. Submitted by: Lt, Col. F. S. Brackett, SnC Major Lester B. Roberts, SnC Captain Wendell E. Mann, MAC APPROVED 3Y _ WILLARD MACHLE Colonel, Medical Corps Commanding 2 Inclfo Appendix - Incl0 #1 Ind0 1 thru 7 - Incl0 #2 2 APPENDIX Certain of the requirements of a tank helmet are clear: These are: 1. Crash protection 2. Comfort, 3. Integration with other head apparel, 4. Integration with sights, periscopes, tank ceiling and gun recoil guard to afford reasonable clearances when performing duties in tanks 5. Ballistic protection when head is outside tank. These requirements, with the exception of 5, are reasonably well satisfied by the Quartermaster helmet liner under consideration. No, 5 can be satisfied, using the Quartermaster liner, only by providing an auxiliary steel helmet to fit over the Quartermaster liner. The steel helmet may be the standard Ml steel helmet or the modified Ml Ordnance steel helmet now being developed. The 1DL.steel helmet is not satisfactory inside the tank because it does not satisfy requirements 3 and 4o The Ordnance modification could be worn inside the tank since it is designed to meet requirements 3 and 4 above, so far as is possible. If steel helmets are to be worn outside the tank and not inside, crew members will be required to remove the helmets each time they button up. More important, convenient stowage space for the steel helmets inside the tank will have to be found. Such stowage space is not now provided. Outside stowage is reported to be impractical. As regards ballistic protection, the commander and driver are most concerned. The commander especially finds it necessary to have his head out of the turret much of the time. He does not have time to remove and stow the steel helmet when he is inside. He must then wear the steel helmet inside the tank at such times. The Quartermaster liner plus development Ordnance steel helmet or Ordnance development one-piece armored helmet would meet his requirements. When Ordnance development helmets are completed and tested it will be possible to appraise some of the problems considered above and arrive at a doctrine of procedure for the tank crew members. Incl, #1 421 - GNOFB 1st Indo JWS/km THE ARMORED BOARD, Fort Knox, Kentucky0 26 Jun 1945* TO: Commanding Officer, Armored Medical Research Laboratory, Fort Knox, Kentucky,, lo The latest version of the Quartermaster tank helmet referred to in basic report appears to satisfy all the specifications listed in 2nd Indorsement, Headquarters, Army Ground Forces, file 42102 GNRQT -6/21942, dated 24 April 1945, and 3rd Indorsement, Headquarters, armored Center, file 420/l GNREE, dated 1 May 1945, except that the built-in earphones are not presento 2® The Armored Board concurs in paragraph 4 of subject report, with the exception that the latest version of the Quartermaster tank helmet not be considered satisfactory until such time as it has been comparatively test- ed with: a„ The one-piece steel helmet, and b0 The tank helmet with built-in earphones0 /s/ Vo 0o Barnard Lt0 Colo FA for /t/ LOUIS Ve HIGHTOWER Colonel, Field Artillery President 1 In do n/c SPMEA 727-121 2nd Ind Armored Medical Research Laboratory, Fort Knox, Kentucky, 7 July 1945« To: President, Armored Board, Fort Knox, Kentucky,, lo Reference is made to Armored Board Report No0 680, ’’Test of Tank Helmet T19E1”, 9 April 1945, paragraph 4, item b„ The helmet T19E1 recommended for adoption as an interim measure is the Quartermaster helmet referred to in AMRL report #24 - prior to modification along 15.nes recommended by Armored Boards 20 Reference 3rd indorsement, 420/1 (31 March 45) GNREE, paragraph 2 b, unless the requirement for ballistic protection is to be reconsidered at this time there does not appear to be any point in delaying procurement of modified helmet T19F.1, as per 1st indorsement this letter (Armored Board paragraph 2)„ As pointed out in appendix of AMRL report #24, a one-piece helmet with ballistic protection may offer an adequate solution but would Incl. #2 (2nd Ind0j7 July 1%5, AiifiL, to President, Armored Board, Ft* Knox, Ky0) require reversal of decision previously made0 3a To our knowledge no helmet with built-in earphones is in development at present timc0 There is an immediate need for production of a crash helmet and subject helmet is believed to be the best now available* /s/ Willard Machle /t/ WILLaRD MACHLE Colonel, MC Commanding 1 Incl: n/c Inclo #2 421o2 GNOFB 3rd Indo L3C/wmt THE ARMORED BOARD, Fort Knox, Kentucky,, 26 Jul 1945® To: Director, Armored Medical Research Laboratory, Fort Knox, Kentucky0 lo The armored Board concurs with the opinion expressed in Paragraph 4 of 2nd Indorsement and recommends that the subject equip- ment be approved for production as limited standard 0,, 2o The desirability of a tank helmet having built-in ballistic properties seems obvious, and the practicability of building such a helmet of lighter weight than the combination helmet and helmet liner seems apparento The practical disadvantage of a two-piece helmet is apparent to all personnel who have been closely associated with tank combat0 The disadvantage of stowing several steel helmets within a tank with all the consequent inconveniences to pv rsoanel and operations within a closely confined space, is exceeded only by the impracticability of attempting to require tank personnel to search for and put on their steel helmets every time they dismount0 Combat experience indicates that something in the neighborhood of 50$ of casualties to tankers occur while they are outside of tanks; the advantage of head protection at such times is agreed upon by all concerned0 any contention that tankers can be required uniformly to put on steel helmet shells before dismounting from a tank implies a lack of knowledge of battle behaviour; while men will do so in situations in which they feel themselves to be in danger, even veteran soldiers can not recognize potentially dangerous situations with a sufficiently high degree of consistency, and inexperienced troops always "learn the hard wayM0 36 The development of a satisfactory tank helmet, including ballistic protection, is a typical equipment problem involving a decision whether to (1) Adopts piece of equipment ill-adapted to use with equip- ment with which it is intended to be used, i0e0, the tank, the use of which requires additional diciplinary training and assumes, fallaciously, a state of discipline which never exists on the battle field or, (2) To insist upon the development of equipment that fits the reeds of the soldier, the limitations of his vehicle and his behaviour characteristics when in combatD /s/ Louis Vo Hightower /t/ LOUIS Vo HICHTOWER Colonel, Field artillery President 1 Incl; n/c Incl, #2 SPMEA 727-121 4th Ind0 LER/srr Armored Medical Research Laboratory, Fort Knox, Kentucky, 14 August 1945 To: President, Armored Board, Fort Knox, Kentucky, 22 Aug 1945* 10 Reference is made to par 2 and 3 of armored Board 3rd Indorse- ment o The Armored Medical Research Laboratory concurs with the reasoning and basic combat logic applied and has expressed the difficulties in dif- ferent form in the body and appendix of the basic report0 2, As regards need for ballistic protection, both the Armored Board and the Armored Medical Research Laboratory views appeal to be in disagree- ment with AGF report of requirements in Europe (see par d, 2nd Indorsement 421o2, 31 Mar 45, GNRQT-6/21942 and par 2-fc, Headquarters Armored Center, 3rd Indorsement, 420/1, 31 Mar 45, GiMREE) 0 Clearly what is needed is a full concise statement of requirements and a firm decision for future helmet consideration. 3o In view of the agreement for approval on limited standard basis it is suggested that basic report be sent on its way and action be taken by all interested parties to get together and iron out difficulties out- lined in par 2 above0 /s/ Willard Machle /t/ WILLARD MACHLE Colonel, UC Commanding 421 GNOFB 5 th Indo JWS/wrnt THE ARMORED BOARD, Fort Knox, Kentucky, To; Commanding Officer, Armored Medical Research Laboratory, Fort Knox, Kentucky. The Armored Board concurs in the recommendation set forth in paragraphs 3, Uth Indorsemento /s/ Louis Vo Hightower /t/ LOUIS V. HIGHTOWER Colonel, Field Artillery President 1 Incl: n/c Incl, §2 SPMEA 727-121 6th Indo CES/srr ARMORED MEDICAL RESEARCH LABORATORY, Fort Knox, Kentucky, 10 September 1945 TO: Commanding General, Headquarters, armored Center, Fort Knox, Ky„ Transmitted herewith for recommendation and/or concurrence one (l) copy of Project No0 24 - Study of Head Protection for Tank Crews - dated 13 June 1945o FOR THE COMMANDING OFFICER: /s/ Charles E0 Stickler /t/ CHARLES Eo STICKLER 2nd Lto, MrtC Adjutant 1 Incls n/c 319ol (18 Jun 45) GNHEE 7th Indo HQ CENTER, Fort Knox, Ky, 13 Sep 1945 TO; Dir, Armd MRL, Fort Knox, Ky lo This headquarters concurs in the recommendations of paragraph 3» 4th indorsements 2o It is apparent in digesting the contents of the preceding indorse- ments, that a clearly defined statement of characteristics is essential be- fore further research is undertaken,, FOR THE COMMANDING GENERAL: 1 Incl: n/c /&/ R0 F0 Rickard /t/ Ro F0 RICKARD Lto Col o , Ho O o D o j Adjutant General0 Incl* #2