Aircraft Vulnerability to Missiles


The answer to this question can be incredibly detailed, especially when written by someone who works in the field of aircraft survivability. Aircraft survivability is the discipline that studies the "ability to withstand and avoid a manmade threat environment." For those of you who are terribly impatient, the short answer is: "Of course an airplane can still fly after it is hit by a missile." It hardly takes a rocket scientist to figure this one out! After all, it was in November of 2003 when a DHL Airbus A300 was struck by a surface-to-air missile and successfully landed at Baghdad International Airport. Of course, the size of the plane and the missile do make a difference, and where the plane gets hit is probably even more important, but the answers to those questions require a bit more complexity.

DHL Airbus A300 being attacked by a shoulder-launched IR guided missile
DHL Airbus A300 being attacked by a shoulder-launched IR guided missile

The area of survivability that is the most relevant to this discussion is vulnerability. Vulnerability is the ability of an aircraft to continue to function even after suffering a hit from an enemy threat. This damage could be caused by anything from simple small arms fire to an advanced surface-to-air missile (SAM). When engineers design an aircraft, especially a military aircraft, they strive for a low vulnerability design. Before we can really determine how to go about giving a new aircraft low vulnerability characteristics, it is best to consider what systems on that aircraft contribute to its vulnerability. These are the five biggest concerns:

  1. Crew system (pilot and copilot)
  2. Flight control systems (control surfaces and hydraulics)
  3. Fuel systems (fuel tanks and fuel lines)
  4. Power train systems (propellers and rotors)
  5. Propulsion systems (engines)

F-18 that survived a missile hit to one of its engines
F-18 that survived a missile hit to one of its engines

After looking at this list, we can start to figure out how to design an aircraft in order to reduce its vulnerability. The main strategies for reducing vulnerability include redundancy, separation, and protection. Redundancy suggests having more than one item that can do the same job. If you lose one, you have a backup. Separation ties into redundancy, as it is best to have the redundant items widely separated so that a single threat cannot disable both. Protection includes armoring a vital component such that it is more difficult to damage. However, armoring isn't always preferred on aircraft since adding weight is rarely a good thing. Below are some examples of how these strategies are often applied to counter each of the "big five."

1. Crew system:

2. Flight control systems: 3. Fuel systems: 4. Power train systems: 5. Propulsion systems: After looking at these protection strategies, one might ask for a good example of a low vulnerability aircraft. The B-17 of World War II is a good historical example. There are many stories of B-17s returning from missions with massive damage, but they were able to remain in the air and bring their crews home.

B-17s that survived extensive damage during World War II
B-17s that survived extensive damage during World War II

A modern example, and arguably the most low vulnerability aircraft in the world today, is the A-10 Warthog. This aircraft has become famous for the considerable damage it took during the Gulf War and more recent conflicts while still being able to return home safely.

A-10 damaged by small arms fire during Operation Iraqi Freedom
A-10 damaged by small arms fire during Operation Iraqi Freedom

So, to answer the question that was asked, where a missile hits a plane is much more important than the size of the plane. While it could be argued that being big has its advantages, since one missile is less likely to damage multiple systems, a larger plane tends to be slower and less maneuverable, presenting a very nice target that is easier to hit.

Now for round two--which kinds of missiles are more dangerous. Again, this is a complex issue that depends on several variables. First, we will consider the two basic types of missiles. What you call heat guided missiles are more accurately referred to as IR guided missiles since they home in on infrared energy. Radar guided missiles are usually called RF guided missiles since they track radio frequency energy.

Since radar is better at tracking targets from great distances, RF guided missiles are usually used over much longer ranges. These missiles are therefore typically larger and more expensive than their IR guided counterparts. Consider the SA-2, for example, which many a Vietnam era pilot referred to as a flying telephone pole, and it is certainly no exaggeration! Infrared radiation, on the other hand, is best used for guidane on short range missiles. IR guided missiles, such as the man-portable Stinger, are typically much smaller with less powerful warheads than RF guided missiles.

SA-2 RF guided surface-to-air missile
SA-2 RF guided surface-to-air missile

So, if we were to look at only the lethality of a missile (the amount of damage it can do) then RF guided missiles would be the most dangerous. However, in the real world today, IR guided missiles and unguided weapons are the primary threat. In the most recent military conflicts, the majority of aircraft kills have been made with IR guided Man Portable Air Defense Systems (MANPADS), such as the Stinger or SA-7. Some of the most publicized kills, like those portrayed in the film Blackhawk Down, have been scored with far less sophisticated unguided weapons like rocket propelled grenades (RPGs).

Stinger man-portable IR guided surface-to-air missile
Stinger man-portable IR guided surface-to-air missile

The effectiveness of MANPADS and unguided weapons can be attributed to three main reasons: cost, simplicity, and stealthiness.

Let's now recap and summarize the main points of this answer. This article has covered some of the basic concepts of aircraft survivability. For additional information on this subject, readers are referred to Dr. Robert Ball's book The Fundamentals of Aircraft Combat Survivability Analysis and Design.
- answer by Doug Jackson, 23 May 2004

Related Topics:


Read More Articles:






Back Aircraft | Design | Ask Us | Shop | Search Home
About Us | Contact Us | Copyright 1997-2012