An air assault operation is a "
deliberate, precisely planned, and vigorously executed combat operation" that is designed to strike the enemy when and where they are most
vulnerable. The
101st Airborne Division stands as the US Army's only air assault division. There are many advantages to an air assault, including the ability to
attack from any direction,
bypass obstacles and strike otherwise inaccessible areas, and concetrate, disperse, or even redeploy troops (generally, its a very flexible
tactic). There are five steps to such an operation:
- The ground tactical plan (GTP): Defines the mission's objectives.
- The landing plan: Defines the landing zones.
- The air movement plan: Defines how the forces will be transported to their landing zones.
- The loading plan: Loads the necessary forces onto the appropriate transportation.
- The staging plan: Organizes the forces and establishes the pickup zone (where the forces will be loaded)
Its worth noting that while these steps must be planned in this order, they are listed in reverse order of
execution. In other words, the ground tactical plan must be set before you can devise a landing plan, which, in itself, drives the loading and staging plans. Yet, you must stage and load your troops before you can land and carry out your objectives.
The Ground Tactical Plan (GTP)
This plan designates the details of the
mission. It sets the objectives of the mission, defines what forces are required (or available), and what tasks those forces will perform. Most of the
details of the mission will be outlined here.
Landing and Air Movement
As previously mentioned, the GTP will define the details of the mission, including the placement of the landing zones and the method of transportation that will be used to deliver the
troops.
There are typically two different types of landings:
- Landing away from the objective: This is the most common version, as it is dependant on incomplete intelligence on things like terrain, weather, enemy forces (and their placement), and the local populace. Other factors that must be considered include whether or not time is available to allow the troops to travel to their objectives or not. The intent is to land all troops and move towards the objective with the maximum force available.
- Landing on the objective: Conversely, this is the less common version, as it requires precise intelligence on the enemy forces, the terrain (specifically the landing zones), weather, etc... Time is generally of the essence in such an operation. Upon landing, the intent here is to immediately and aggressively engage the enemy in an attempt to secure the objectives.
It is imperative that the attacking forces land ready to fight. The landing is the most
critical part of an air assault as it is when the attacking forces are most vulnerable.
Suppressing fire from supporting forces (
naval guns, close air
support, attack
helicopters, etc..) is also necessary in order to
facilitate the landing.
Once the landing zones (and their alternates; theres always a backup) are set, an air movement plan is designed to provide transportation for the troops. There is usually one approach
flight path with a different
departure flight path. The plan is designed to avoid known enemy
air defenses and to provide appropriate
suppressing fire for the landing operations (for both the
primary and
alternate landing zones).
Today, the most common method of delivery for air assault forces is the
helicopter (a force with this capability is said to be
airmobile). The advent of the helicopter allowed a great deal of
flexability when planning operations. The idea is that a
commander of an airmobile unit does not have to keep up a traditional
reserve. They can simply extract a reserve out of their deployed units as needed.
That being said, airmobile capabilites only came into being during the
Vietnam war (though there were some fundamental decisions that were made in the decade preceding that war). In
World War II, the basic plans were the same, but their methods of transportation were more limited.
Three methods were used during World War II to land troops:
parachutes, transport
gliders, and transport planes. All three methods were used in the war, though it was found that the last method was ill-suited for the initial capture of enemy territory from the air;
paratroopers and
gliderborne troops were better suited for such a mission.
A glider's main
advantage is that it delivers its entire attack force in one place, which immediately allows them to operate as a unit ready for
combat. Paratroopers, on the other hand, are generally spread out more over an area, and thus require some time to
assemble and organize. Paratroopers are also able to change their drop point at any time during the attack, allowing them to react to changing circumstances. Gliders are released far from the objective, and once released, cannot change their landing area. However, since gliders also move
silently, they are often considered to make a good
initial attack that is meant to be followed by mass parachute jumps.
Again, from Vietnam to present times, air assault forces use helicopters for
insertion. One typical insertion
technique is to simply land the transport helicopter and have the attack force hop out (
extraction works in a similar manner). Another insertion technique is to have troops slide down ropes while the helicopter
hovers at about 100ft (or lower). This is called
rappelling, and there are several techniques that can be used. The most common method dictates that rappellers exit the helicopter at a rate of one every five seconds. With the
Fast Rope Insertion and Extraction System (FRIES), rappellers exit at a rate of one every second. FRIES is excellent for the isertion of small units in confined areas, but is inherantly dangerous and it is not uncommon for major injuries to occur (and the time of landing is the worst possible time as the troops are at their most vulnerable). It is for this reason that FRIES is limited to missions where no landing is possible. Often, an attack force will send various equipment and supplies down the rope, which is called
rigging or
sling loading.
Loading and Staging
An air assault does not
succeed when executing its loading and staging procedures, but it can certainly
fail there. This is where all of the combat units are organized and separated into small attack forces, each of which must be a
self-contained force that understands what it must do on landing at either the primary or alternate landing zone.
Disadvantages and Limitations
Since air assault operations depend mainly on helicopters and other aircraft, they are limited by such things as adverse weather, heavy enemy anti-aircraft defenses, and availability of suitable landing zones. Also, helicopters don't quite have the range that large aircraft do, and they tend to use more fuel. Also, as previously mentioned, the attack force is particularly vulnerable during the landing phase of the operation.
Sources:
http://www.adtdl.army.mil/cgi-bin/atdl.dll/fm/90-4/toc.htm
http://www.fas.org/man/dod-101/army/docs/101st-goldbook/index.html
http://www.army.mil/cmh-pg/books/Vietnam/Airmobility/airmobility-fm.html
http://avstop.com/History/WWII/3.htm
http://www.adtdl.army.mil/cgi-bin/atdl.dll/tc/21-24/toc.htm
http://www.safetycenter.navy.mil/media/groundwarrior/issues/Winter01/nexttime.htm