Still being looked at

Friendly fire deaths traced to problems with Patriot

During the initial invasion of Iraq, MO was keeping tabs on Patriot missiles shooting down friendly aircraft. (See this, this, this, this, and this.) One American and one British plane was shot down, and another American plane was targeted before the plane took out the Patriot’s radar.

The latest-generation Patriot, the PAC-3, had skipped its operational testing phase. I’ve long wondered which model (PAC-2 or PAC-3) shot down which plane and if the lack of operational testing may have contributed to the problems which led to the tragic errors.

A Defense Science Board task force was formed in August of 2003 tasked with studying the performance of the Patriot in Operation Iraqi Freedom and determining whether any of the lessons learned would be applicable to the MEADS air defense program, the successor to the Patriot:

Patriots appear to have shot down nine incoming Iraqi short-range ballistic missiles during the invasion, says a summary of the report.

But Patriot batteries also misidentified and shot down an American and a British fighter in separate incidents, leaving three air crew members dead. A Patriot system also mistakenly tracked another U.S. fighter, which bombed a radar in response. The incidents took place in March and April 2003.

The report, posted on a military Web site this week, was authored by a task force of the Defense Science Board, which advises Secretary of Defense Donald H. Rumsfeld on a range of issues.

In general, the report attributes The friendly fire incidents to the technical difficulty of tracking a single incoming missile among the hundreds of friendly aircraft that flew sorties during the early part of the war.

Three primary “shortfalls” were identified:

  1. The IFF (Identification Friend or Foe) system performed “poorly”.
  2. Communication and coordination between various air defense systems was poor, leaving Patriot batteries on their own instead of plugged in to the overall situation.
  3. The entire software-based automatic concept of operations was a poor match for the conditions in OIF, where friendlies in the sky outnumbered enemies 4,000 to 1, and human operators basically trusted the computers to decide if and when to fire.

None of this is really new information, of course. The report summary includes

The Task Force had recommendations in three areas. With regard to the fratricide incidents, we must find and fix the Mode IV IFF problem(s) and we must improve the situational awareness of our air defense systems. With regard to the Patriot system itself, we need to shift its operation and control philosophy to deal with the complex environments of today’s and future conflicts. These future conflicts will likely be more stressing than OIF and involve Patriot in simultaneous missile and air defense engagements. A protocol that allows more operator oversight and control of major system actions will be needed.

I’ve mentioned previously that the National Missile Defense system is being rushed through its own operational testing phase, and that the problems encountered so far in development are eerily similar to those encountered by the Patriot.

What will happen if/when an NMD interceptor shoots down a civilian airliner?

The Patriot report itself is classified, but a .pdf of the report summary is available here. I will include the main text of the summary in the extended entry section of this post.

Report of the
Defense Science Board Task Force on Patriot System Performance

Report Summary
January 2005
Office of the Under Secretary of Defense
For Acquisition, Technology, and Logistics
Washington, D.C. 20301-3140

This report summary is a product of the Defense Science Board (DSB). The DSB is a
Federal Advisory Committee established to provide independent advice to the Secretary
of Defense. Statements, opinions, conclusions, and recommendations in this report
summary do not necessarily represent the official position of the Department of Defense.
This report summary is UNCLASSIFIED.

Introduction
The Defense Science Board Task Force on Patriot System Performance began
in August 2003 and concluded in June 2004. The Terms of Reference for the Task
Force are given in Appendix A, the Task Force Membership is in Appendix B, and the
briefings given to the Task Force are listed in Appendix C. This is the Report Summary.
The complete Final Report is classified.
The Task Force investigated the lessons learned from the Patriot system
performance in Operation Iraqi Freedom (OIF) and assessed if these lessons could be
incorporated into the continuing development of Patriot and its follow-on system, the
Medium Extended Air Defense System (MEADS). The Task Force concluded that the
lessons can be incorporated into Patriot-MEADS. Two of the main shortfalls seen in OIF
performance transcend just the Patriot system; they involve combat identification and
situational awareness.

Patriot Missile Defense
The Patriot role in OIF was defense against tactical ballistic missiles; it had no
assigned air defense role, but it did have a self-defense role against anti-radiation
missiles. The Patriot deployment was substantial, involving up to 40 U.S. fire units and
22 fire units from four coalition nations. Two types of Patriot interceptor missiles were
used: the improved PAC-2 missile, which is the traditional Patriot interceptor; and a new
hit-to-kill missile, the PAC-3. Both were used with success in OIF, with the bulk of the
engagements falling to the PAC-2. All nine enemy tactical ballistic missiles that
threatened areas designated for Patriot defense were engaged. Eight of these
engagements were observed by enough other sensors to conservatively declare them
successes; the ninth engagement is judged to be a probable success. None of the
attacking tactical ballistic missiles caused any damage or loss of life to the coalition
forces.
The Patriot battalions operated reliably, and the two variants of the interceptor
missile worked well against these Iraqi tactical ballistic missiles. One can argue that
these relatively slow missiles which did not break up in flight like the Scuds of Desert
Storm, were not stressing targets; however, their short range and the coalition’ goal of
large defended footprints and high-altitude intercepts due to chemical warhead concerns
made them somewhat stressing targets for the Patriot and their crews.
In an overall sense, the Task Force assessed the Patriot missile defense in OIF
to be a substantial success.

Fratricide Incidents
The Patriot system was involved in three regrettable fratricide incidents. Two of
these incidents involved Patriot firings at coalition aircraft that in one case was classified
as an attacking anti-radiation missile and an attacking tactical ballistic missile. Three
aircraft crew members were lost in these two incidents. The third incident involved a
U.S. aircraft firing on a Patriot battery believed to be an enemy surface-to-air missile
system.
These incidents generally involved a complex chain of events and failures, and
there is often insufficient data to pin down the exact causes of failure. However, a
number of shortfalls can be identified.
First, our combat identification capability embodied in the Mode IV IFF system
performed very poorly. This is not exactly a surprise; this poor performance has been
seen in many training exercises. The Task Force remains puzzled as to why this
deficiency never garners enough resolve and support to result in a robust fix. The
number of coalition aircraft flights in OIF was enormous, 41,000, and the Patriot
deployment was large, 60 fire units, so the possible Patriot-friendly aircraft observations
were in the millions and even very-low-probability failures could result in regrettable
fratricide incidents. We have to fix Mode IV and institute additional protection measures
such as safe return corridors for our aircraft.
A second shortfall was the lack of significant situational awareness in our
combined air defense system, which involved major systems such as Patriot, AWACS,
and AEGIS. We tend to assume that data are routinely communicated from one system
to the other, that targets are correlated, and target information is shared and assimilated
by all. The Task Force believes that we are a long way from that vision. The
communication links, the ability to correlate target tracks by disparate sensors, and the
overall information architecture are simply not there. Thus, a Patriot battery on the
battlefield can be very much alone. Its closest connection is its Patriot battalion
headquarters unit, and in some cases in OIF even that connection was weak.
The third shortfall was the Patriot system operating philosophy, protocols,
displays, and software, which seemed to be a poor match to the conditions of OIF. The
operating protocol was largely automatic, and the operators were trained to trust the
system’s software; a design that would be needed for heavy missile attacks. The 30
days of OIF involved 9 engagements of tactical ballistic missiles which were immersed in
an environment of some 41,000 coalition aircraft sorties; a 4,000-to-1 friendly-to-enemy
ratio.
The solution here will be more operator involvement and control in the
functioning of a Patriot battery, which will necessitate changes in software, displays, and
training.

Patriot-MEADS Development
The Task Force was asked to comment on the ongoing Patriot and MEADS
programs, which recently were combined into a single program. The main question was
– could the planned program assimilate the lessons learned in OIF?
The basic architecture of MEADS calls for a high degree of connectivity to other
air and missile defense systems. This, plus the MEADS battery design with three radars
with 360 degree coverage capability, should provide a high degree of situational
awareness.
The recently combined Patriot-MEADS program plans a gradual infusion of
MEADS software and components, so that in the 2015 era the Patriot system will have
fully migrated to MEADS. The interceptor missile will be an improved version of the
PAC-3. The Task Force believes this multi-year migration from Patriot to MEADS will be
a challenging task. Adding to the challenge will be the relatively unique acquisition
program that involves several European firms developing and producing major
components of the MEADS system, in addition to U.S. firms.
During this long development-acquisition period, we need to upgrade and
maintain our Patriot batteries, since they will be our main air and missile defense well
into the future.

Recommendations
The Task Force had recommendations in three areas. With regard to the
fratricide incidents, we must find and fix the Mode IV IFF problem(s) and we must
improve the situational awareness of our air defense systems. With regard to the Patriot
system itself, we need to shift its operation and control philosophy to deal with the
complex environments of today’s and future conflicts. These future conflicts will likely be
more stressing than OIF and involve Patriot in simultaneous missile and air defense
engagements. A protocol that allows more operator oversight and control of major
system actions will be needed.
With regard to the Patriot migration to become MEADS, the Task Force
recommends a conservative course where we maintain a robust Patriot system as
MEADS components are developed, proven, and integrated into Patriot battalions.