Load 'Em Up

Ever wondered who flew on what in an Air Assault, or how many helicopters you are going to need to put your Company into that LZ? This Explanation of 'official' methods used for determining aircraft requirements and loads just might help you out.

This article discusses the methods used to determine Army aircraft requirements and loads based on an announced allowable cargo load (ACL). The methods discussed here are also applicable to establishing Air Force aircraft requirements and loads.

Factors Affecting Aircraft Determinations

When planning for an airmobile operation or a movement by air, commanders and staff officers must be familiar with the type and characteristics of aircraft available for the move. To determine the number of aircraft required for any given mission, the following must be considered:

1. Dimensions and location of the cargo door and the dimensions of the cargo compartment.
2. Allowable cargo load of the type aircraft for the mission. This is provided by the supporting aviation commander based on technical considerations.
3. The number of personnel, amount of equipment, and the amount of supplies to be airlifted.
4. Standard individual weights.

For airmobile operations and tactical airlifts, the standard weights for individuals as shown below are used. These weights take into consideration the weight of the man plus his combat equipment and proportionate share of hand-carried supplies and TOE equipment.

1. Aircraft crewman - 200 pounds.
2. Combat-equipped soldier - 240 pounds.
3. Litter patient - 250 pounds.
4. Parachutist - 260 pounds.

During the strategic deployment of units, the weight of the individual soldier is much harder to determine since the hand-carried equipment and supplies will vary with the type of deployment, climate. and purpose of the mission. Under such circumstances, a standardized weight should be computed and agreed upon by both the supported and supporting commanders.

Methods used to Determine Aircraft Requirements

When those factors listed above have been considered and non-transportable items have been eliminated or replaced with transportable items, three methods may be used to determine aircraft requirements:

1. The weight method.
2. The type load method.
3. The space method.

Weight Method

a. The weight method is normally used at division or higher level of command to estimate air-craft requirements rapidly. This method is based on the assumption that total weight of the force to be moved will be the determining factor. It is not accurate enough to compute requirements for units in which major items of equipment are to be transported and tactical integrity is to be maintained.

b. Aircraft requirements are determined by dividing the allowable cargo load (payload) of each type aircraft to be used into the total weight of the force to be airlifted. Whenever the weight method is used, care must be taken so that anyone load does not exceed the ACL of the aircraft being used and that no one piece of equipment exceeds the size and weight limit of the aircraft.

c. Examples:

• Weight to be transported = 73,800 lbs.
• Allowable cargo load, each CH-47A = 6,000 lbs.
• 73,800 / 6,000 = 12.3, or 13 CH-47A's required.

• Weight to be transported = 60,970 lbs.
• Allowable cargo load, each UH-1H = 1,700 lbs.
• 60,970 / 1,700 = 35.8 or 36 UH-1H s required.

Type Load Method

a. This method uses type load arrangements of personnel and/ or cargo to load a specific air-craft with a specific allowable cargo load. Each time the type aircraft changes or there is a change in the announced allowable cargo load, the type load arrangement will have to be modified.

b. The type load method is the most accurate method of determining aircraft requirements for Army and Air Force aircraft. It is particularly valuable for determining requirements for small units which are to be loaded on Army aircraft.

c. Sample Type Loads: The following type loads are examples of loads which can be carried on the various types of Army aircraft under normal conditions in Vietnam. Weight limitations will vary from one mission to another as atmospheric conditions change. Reducing fuel loads on the aircraft will also increase carrying capabilities. Other variables such as the size and shape of loading/landing zones will affect allowable cargo loads. The following examples are only a guide.

Example 1: Type loads for a UH-1D/H with an allowable cargo load of 1200 lbs and 2+30 hrs of fuel.

Example 2: Type loads for a UH-1D/H with an allowable cargo load of 2100 lbs and 1+00 hrs of fuel.

Example 3: Type loads for a CH-47A with an allowable cargo load of 8,000 lbs and 1+50 hrs of fuel.

Space Method

a. This method is a simplification of the weight and type load methods and is used to determine Army aircraft requirements. The weight of a combat equipped soldier, 240 lbs, is used as a denominator to convert weights into spaces. This 240 lbs includes the weight of the individual and his proportionate share of hand-carried supplies and equipment, to include crew-served weapons up to, but not including, the 106mm rifle and 4.2-inch mortar.

b. To convert major items of equipment into spaces, the weight (in pounds) of the individual item is divided by 240. If two or more items of the same type are to be transported, the number of spaces required for a single item is multiplied by the number of items. In converting transported weight to spaces, consider only whole or half- spaces. Carry fractions to next higher half-space (10.1 = 10.5, 11.6= 12). Example:

• 1/4 ton truck = 2665lbs
• 2665 / 240 = 11.1 or 11.5 spaces
• Number of items = 2
• 2 x 11.5 = 23 spaces total

c. To convert additional assault supplies (not carried by the individual soldier) into spaces, the total weight of those supplies (in pounds) is divided by 240. Example: 3048 (total weight) / 240 (space) = 12.7 or 13 spaces

d. To convert the allowable cargo load of an aircraft into spaces, the allowable cargo is divided by 240. In converting allowable cargo loads to spaces, consider only whole or half-spaces. Fractions will be reduced to the next lower half-space, i.e. (22.8 = 22.5, 24.3 = 24). Example: 2553 (allowable cargo load, single aircraft) / 240 = 10.6 or 10.5 spaces ea. aircraft

e. To determine the number of aircraft required to airlift a force, the total number of spaces required is divided by the allowable cargo load of a single aircraft expressed in spaces. Example: 251 (spaces required) / 10.5 (spaces available ea. aircraft) = 23.8 or 24 aircraft required

Typical Air Loading Table

A typical air loading table for moving a dismounted infantry rifle company in the UH-1H would be computed in the following manner:

a. For the purpose of this example the rifle company has six officers and 174 EM (Total = 180). Five personnel are considered nonessential and are not taken initially into the objective area. One senior aid-man is attached to the company. This makes the company total personnel strength 176.

1. Co Hq (x1): 1 Co Cmdr, 1 Comm Chief, 2 RTO, 2 Wiremen, 1 Snr. Aid-man, 1 Radio Mech. = 8 (Total 8)
2. Rifle Platoon Hq (x3): 1 Plat Ldr, 1 Plat Sgt, 1 RTO = 3 (Total 9)
• Rifle Sqd (x9): 1 Sqd Ldr, 2 Tm Ldr, 2 Auto Riflemen, 2 Grenadier, 3 Riflemen = 10 (Total 90)
• Wpns Sqd (x3): 1 Sqd Ldr, 2 Mg Gnr, 2 90mm Gnr, 2 Ammo Bearer, 2 Asst Mg Gunner, 2 Asst 90mm Gunner = 11 (Total 33)
3. Wpns Plat Hq (x1): 1 Plat Ldr, 1 Plt Sgt, 1 RTO = 3 (Total 3)
• Antitank Sqd (x2): 1 Sec Ldr, 1 Sqd Ldr, 1 Gnr, 1 Ammo Bearer, 1 Asst Gunner = 5 (Total 10)
• 81mm Mort Sec Hq (x1): 1 Sec Ldr, 3 Fwd Obsr, 2 FD Cmpt, 3 RTO = 9 (Total 9)
4. Rear Echelon (x1): 1 XO, 1 1SG, 1 Sup Sgt, 1 Armorer, 1 Co Clerk = 5 (Total 5)

b. A rifle company will normally carry into the objective area 48 rounds of 81mm ammunition per tube (3 x 48 = 144 rounds; 15 pounds per round) and 12 rounds of 106 mm recoilless rifle ammunition per 106mm recoilless rifle (2 x 12 = 24; 37 pounds per round).

c. The planning worksheet is used to assist in space method computations and in preparation of the air loading table.

d. The preparation of the air loading table for a unit, such as a rifle company, is normally the responsibility of the unit commander. He consults with the appropriate staff officers as necessary. At brigade level, the aviation section commander, who is also the special staff officer on Army aviation matters, normally will be called upon to assist in the preparation of an air loading table. He usually assists in the area of technical characteristics and capabilities of Army aircraft.

e. The senior ground force occupant of each aircraft is responsible for insuring that personnel and equipment are loaded on the aircraft in accordance with the air loading table.

f. In preparing a unit's air loading table, consideration must be given to:

1. Insure unit integrity to the extent possible.
2. Distribute key personnel and critical equipment among several aircraft.
3. Personnel in each aircraft to unload equipment carried internally or externally.
4. Intended landing area in the objective area, and the unit's mission.

g. See opposite for a type air loading table using UH-1H's with an allowable cargo load of 2400 (10 spaces) and 1+30 hours of fuel.

Planning Worksheet

Total Spaces = 189 (Total columns 2, 4 and 9)

Total Aircraft Required = 19 (189 / 10 [No spaces per aircraft] = 18.9 or 19)

* Items of equipment that are to enter the objective area in the follow-up echelon or remain in the rear echelon are computed in the initial planning. Therefore, equipment that cannot accompany the assault echelon, if needed later, can be readily moved by CH-47 without further complications.

Wargaming a Combat Air Assault

Despite the huge numbers of helicopters deployed in Vietnam, helicopter assets were still thinly spread. Books and films tend to suggest that the infantry was routinely lifted and inserted by helicopter companys simply by getting on the radio and requesting it. In fact this was not the case. Company and Battalion sized lifts were rare rather than the norm.

In most instances on routine operations the grunts simply had to hump from point A to point B.

When Combat Air Assaults were ordered they quite often took place using only a platoon of lift ships (6 aircraft) sufficient to carry a single rifle platoon.

In wargaming terms you will probably only have to field six helicopters and shuttle in the company one platoon at a time.

For an excellent account of how a Combat Air Assault was organised and carried out see Charlie Alpha: A Helicopter-borne Combat Assault in Vietnam

Sources

• Airmobility Handbook, US Army Inf. School, Ft. Benning, Georgia, October 1969 (personal collection)