From the Archives

A Mobile Command Post for Field Operations (January 1964)

By Honorable Howard R. Leary
Archive photo of a mobile command vehicle from 1964
Mobile command vehicle, “Car 800”

[Published in its original form]

Commissioner, Major incidents requiring large-scale police activity pose special problems to the police administrator. These incidents, including multiple alarm fires, labor disputes, disasters, intensive crime investigations and manhunts, and large civil disobedience demonstrations, to cite a few examples, require major field operations involving many units of the department.

Problems Involved

Often these incidents are large in size, lengthy in duration, and located at a considerable distance from the headquarters building or another facility. Available communications are usually inadequate to meet the need. In many cases, the command structure at the field operation must, of necessity, be dispersed to various locations at the scene. Usually there is no method of communicating between the various units. The field commander finds it difficult at times to obtain a complete perspective of the incident because of these shortcomings.

The scope and urgency of the situation, when coupled with inadequate facilities and communications, compound the problem of obtaining timely information necessary for evaluating the situation and subsequently taking the necessary action. In general, coordination and direction of the total police effort are hampered under these conditions.

Thus we find that while our normal command organization functions efficiently at headquarters on a routine basis, our field command must function at major incidents under very challenging conditions on an emergency basis. Therefore, we must make some provision that will enable us to effectively meet our responsibilities in these field operations with efficiency comparable to that which our regular command organization provides.

The Mobile Command Vehicle

To accomplish this objective, the Philadelphia Police Department developed “Car 800”, a mobile command vehicle. It was specifically designed to serve as our command center at large field operations. This vehicle provides adequate communicative tools; serves as the center for operational planning, deployment, and evaluation; and, in general, facilitates the command functions in the field.

Archive Photo 3
Commissioner, Philadelphia, Pennsylvania, Police Department

This vehicle is a half-ton panel truck, formerly used as a utility truck before its conversion into a command vehicle. The choice of this size vehicle was based on our desire to have a compact unit that could be used on many types of operations. The selected vehicle provides sufficient room to comfortably house the equipment and personnel needed for its operation. The compactness actually increases its utility because it is more easily and rapidly driven to a location, and the size of the truck lends itself to efficient operation regardless of the size of the incident.

Functioning of the Vehicle

As soon as a major incident develops, “Car 800”, normally headquartered at the police garage, is activated and sent to the scene. The Communications Section of the Department of Public Property, the city agency responsible for installing communications, is promptly notified to send a service crew to the incident location to connect the electrical power lines and arrange for telephone installation when necessary.

The designated field commander determines the command structure, and immediate evaluation and planning are begun. Manpower and equipment needs are determined and obtained from available sources. As a result of the evaluation and planning, personnel and equipment are deployed as the situation requires, and communicative and intelligence needs are analyzed and established.

Operational Planning

Sound decisions and proper action are dependent upon knowledge of the situation. The inherent capacities of the mobile command vehicle, “Car 800”, facilitate the collection and analysis of information from all portions of the emergency scene. This on-the-scene evaluation—converting raw information into meaningful intelligence—provides the field commander with more complete data upon which to base his decision-making and to issue orders.

Continual operational planning and evaluation are necessary in order to maintain maximum effectiveness. The command vehicle meets the need for an on-the-spot location to carry out this planning very effectively.

To facilitate the recording of the data, two typewriters were installed in the command vehicle, and a supply of departmental forms is carried for report preparation. Chronological activity logs and intelligence reports are prepared as the information is received. In addition, the area of each incident is charted and a large diagram of the scene developed. A clear plastic overlay is taped over the diagram. Manpower and equipment deployment is then plotted on the overlay. At a glance, the field commander can assay the deployment in any given area. As the situation develops, he is kept constantly informed of the current condition. Through this evaluation and deployment analysis, he can efficiently coordinate and direct the total police effort to meet the situation.


Archive photo of the interior of a mobile command vehicle from 1964
Interior of converted panel truck.

Equipment installed in the truck includes a radio, telephone, two typewriters, shelving, and cabinets. In addition, lighting equipment, investigative aids, special tools, and other items as required are carried in the vehicle.


The importance of communications at the field operation cannot be overstressed, because they are necessary for effective direction and coordination. We have equipped our command vehicle with three methods: radio, telephone, and walkie-talkie. They enable the field commander to receive and transmit information more rapidly from or to any source than was previously possible. The additional quantity and speed gained enable him to evaluate the situation more quickly and comprehensively.

Radio and Telephone

The radio system permits use of any of the three regular broadcast channels and an additional special ultrahigh frequency (UHF) which we use for field operations only. This special band insures that the messages associated with the field operation will be broadcast without delay or interruption. In addition, the regular broadcast frequencies are not overtaxed in the amount of message traffic carried. It is a duplex system that permits three-way communications on the network.

As conditions warrant, radio-equipped vehicles are deployed at various positions in the field operation, and both relay information and receive instructions from the command vehicle. The radio room at headquarters also participates in the network, insuring speed when information must be relayed to other units of the department or additional manpower or equipment must be obtained from other sources.

The use of a telephone has particular value when it is necessary to communicate directly with other officials and agencies outside of the department, especially if speed and accuracy are mandatory, factors which must at times be sacrificed when information is relayed. Since a telephone line, of course, must be installed at every new location, its use is limited to major incidents.


Another communicative tool utilized is the portable walkie-talkie. This has proved extremely valuable when observation would be advantageous from elevated positions such as rooftops or areas inaccessible to the radio-equipped vehicle. Again, the central station for this method of communication is located at the command vehicle.

In addition to the equipment, a remodeling of the vehicle and the installation of complex electrical systems were done before this transition from a utility truck to a command vehicle was completed.

The remodeling of the interior involved the installation of fiberglass insulation on the walls, floor and, ceiling. These areas were panelled with plywood and then painted. A typewriter shelf, chairs, forms holder, and various cabinets for the other equipment were provided. Overhead lighting and interior convenience outlets on the side panels were installed as well as a rubber-tile floor for durability and ease of maintenance.

The comfort of the occupants was also kept in mind. To provide comfort to and reduce the fatigue of personnel who must work inside the vehicle for any length of time, regular typewriter chairs are used rather than benches or stools. In addition to the insulation, an exhaust fan, all-weather type, was installed in the ceiling for cooling purposes, and an electric, flush-type heater was mounted on a side panel.

Electrical Power Source

Weather-proof convenience outlets were also installed on the exterior panels of the truck. With this arrangement, outdoor lighting apparatus and other emergency equipment can be easily connected to the 110-volt circuit of the vehicle.

Thus the vehicle is equipped to function at any time of the day and in any type of weather.

Because the amount of additional equipment in the vehicle, consideration had to be given to insuring adequate electrical power for its proper functioning. Two separate and independent power sources were developed and the vehicle chassis was then wired to function with either system.

Archive photo of a law enforcement officer using a typewriter in a mobile command vehicle from 1964
Sgt. James Herron types report at one of two typewriters in vehicle.

The first system consists of tapping a nearby public power source, usually a utility pole carrying a 220-volt line. This 220-volt line is then brought into the main circuit-breaker terminal box installed in the vehicle where it is divided into two 110-volt lines, each having the protection of a separate circuit breaker. Most appliance equipment, convenience outlets, lighting circuits, and exhaust fans are factory regulated for 110-volt performance. This system has facilitated their use in the mobile command vehicle. In addition, the UHF radio system, normally regulated for 12-volt battery operation, can be operated on this system (110-volt) by the use of a “tapering-charge” battery charger connected to the circuit terminal box in the vehicle. This innovation allows the radio to be operated without requiring the power of the truck engine, thereby reducing mechanical damage to the engine if it were to operate for a long period of time at idle speed.

The circuit-breaker terminal box can also be converted rather easily, on the scene, to operate on a 110-volt feed line, rather than 220 volts, if that is the only power source available.

Second System

The second electrical system was developed in the event that there should be no public power source available for use or if it is impractical to tap one in the area. This system develops power from the electrical system of the vehicle using two 70 amp/hour automobile batteries, wired in parallel and powered by a 100-amp alternator. The radio circuit (12 volts) operates directly off this system, and a 110-volt circuit is provided by using a 600-watt inverter connected to the battery circuit and wired into the 110-volt circuit-breaker terminal. This electrical system requires the truck engine to be operating to provide the electrical power.

Practical Value of Unit

We have developed our command vehicle in accordance with our needs. This basic idea can be adopted by any department. The size of the vehicle and the amount of equipment to be carried will depend upon local needs and financial capabilities.

The command vehicle has fulfilled its role well and has proved effective when used in our field operations. It has become the nerve center of our field operations and, in a sense, has brought more order and design to our operations. The field organization is well established, with the command vehicle as the field headquarters. The responsibility for each function at a scene is now clearly defined and placed, insuring better performance. Because it coordinates the many needs of a large operation, it has enhanced the teamwork aspect so vital in any large undertaking.

In essence, it provides a focal point at an emergency scene at which command personnel and city officials can be briefed on the existing situation; in which pertinent data can be recorded, reports prepared, and operational planning carried out; and through which effective command control and direction can be exercised.

From the Archives is a new department that features articles previously published throughout the 80-year history of the Bulletin. Topics include crime problems, police strategies, community issues, and personnel, among others. A link to an electronic version of the full issue will appear at the end of each article.