High Speed Drones for ISR / OODA

The role of time and space in ISR and OODA (incident response) integration.

High speed drones. With drones the functional specifications that often receive the most attention typically are: flight time, and payload

But when it comes to longer range missions, long flight times do little to help if the drone. If in responding to an incident, it arrives at a target destination too late and the target situation or environment has changed so much as to render its late arrival to the scene irrelevant.

Changes in relevance of response over time can loosely be categorised as having Imperceptible, Insignificant or Significant impact on the efficacy of a planned intervention. See depiction:

3 different states for response time efficacy
Decay of response time efficacy over time

(The efficacy of a planned intervention would be dependent of available capacity to intervene, ie: level of medical care in a trauma incident, or the Initial Observable Span of a UAV-based sensor in an ISR operation.) 

“Golden Hour”

This notion is most graphically described by the well-known term “GOLDEN HOUR” in a medical context:

“The ‘golden hour‘ is a term often used in trauma. It defines the time that an injured patient has to get to definitive care as 60minutes. After which morbidity and mortality significantly increase.” (State 3: Significant change has occurred)

Golden Hour


ISR (Intelligence, Surveillance, Reconnaissance)  SA (Situational Awareness) OODA (Observation, Orient, Decide, Act)

“Situational awareness (SA) is the perception of environmental elements and events with respect to time or space, the comprehension of their meaning, and the projection of their status after some variable has changed, such as time, or some other variable, such as a predetermined event.”

Situational Awareness

SA is applied to understand the environment critical to decision-makers in complex, dynamic areas. These areas range from aviation, air traffic control, ship navigation, power plant operations, military command and control, and emergency services such as firefighting and policing; pipeline monitoring and remote security operations

SA also involves both a temporal and a spatial component. Time is an important concept in SA, as SA is a dynamic construct, changing at a tempo dictated by the actions of individualstask characteristics, and the surrounding environment

As new inputs enter the system, the individual incorporates them into this mental representation, making changes as necessary in plans and actions in order to achieve the desired goals. SA also involves spatial knowledge about the activities and events occurring in a specific location of interest to the individual. 

Thus, the concept of SA includes perceptioncomprehension, and projection of situational information, as well as temporal and spatial components. 


Incident response

Drones have found to be highly effective and increasingly popular shrinking time and space in ISR applications. Especially in response to detected incidents when time is of the essence to achieve, or maintain, competitive, reliable and consistent SA, before the ‘state’ of SA changes from one significant state to the other (see above). The diagramme below shows the integration of SA with the OODA(Observe, Orient, Decide and Act) loop. 

Situational Awareness and OODA model
SA / OODA integration

Prompt feedback on a situation is crucial to ensure the best-informed responses. Sensors housed on low altitude UAV platforms can achieve such remote situational feedback

Average drones speeds

Currently the inherent design of most commercially available small UAV quadcopters allow speeds in the range of about 60km/hour. These often have flight times of less than 30 minutes. This means they have outbound flight times of less than 15 minutes

There are some long range drone manufacturers that produce drones that can achieve 60 minute flight times with 30 minute outbound flight times. A select few long range specialists that can muster a 60 minute out bound flight time.

Scenario: Searching for Human targets on the ground

Human walking speeds

The distance a person can walk in 15 minutes, 30 minutes and 60 minutes. High speed drones can reduce this time.

The average walking speed for a person is about 5km/hour, in the wilderness it is about 4 km/hour. Which means that in the 15 minutes that it could take a drone to get the point where an alarm was triggered, persons on foot could have walked about 1 km, or 2 kms if the outbound flight was 30 minutes, 4 kms if the outbound was 60 minutes.


Sensor Strength

The power of a sensor is determined by a combination of:

  • Resolution – how far it can detect a human target: which is about 2 kms for HD Zoom, 700m for IR and 1 – 2 km for SAR, 
  • and vertical FOV (Field of View) which can be in the region of 450 for IR, 630 for HD Optical.

As sensors are often used in combination, they could be constrained by one common set of limitations.

Initial Observable Span (Sensors)

Initial observable span is determined by the FOV of the sensor payload of a high speed UAV

Depending on which sensor (IR, HD Optical or SAR) is being used, a field of vision area of between 1km in diameter to 2km across can be observed when arriving at the initial point of detection

Growing Size of Search Area

The difference high speed drones can make to reduce the growing size of a search area

Within 15 minutes of walking the search area to find human targets is 3.14km2. This increases to 12.57km2 after 30 minutes and, 50.27 km2 after 60 minutes

If target/s have moved further than the initial observable span of the AUV-borne sensors it will cause ISR (Intelligence, Surveillance and Reconnaissance) missions to convert to a search mode. This comes with accompanying risk that it becomes  more difficult to find, and to connect targets with the initial point of detection

Sensor Observable Area as % of Search Area at different points in Time.

High speed drones can reduce the search area to that of the initial observable span of the sensor payload

The initial observable span of UAV based sensors reduces from 100% after 15 minutes of the target search area to 25% after 30 minutes and 6% after 60 minutes and the search challenge increases exponentially. All of this assumes the flight speed of standard drones. Clearly with greater speed the efficacy of response (OODA) is greatly enhanced.

Benefits of High Speed Drones

Speed vs. flight time 

At an average speed of 60km/h, conventional UAVs cannot achieve much efficiency if they reach long range targets belatedly after the situation has changed significantly. 

The difference high speed drones make in 15 minutes
Distances covered in 15 minutes

At 200km/h high speed low altitude drones would reach a target 60km away in 15minutes, a conventional UAV would still be 45km and 45 minutes away. The target environment can change unrecognisably during that time.

High speed drones: Other Applications

There are many other long range applications where timeous response is material include the monitoring of Pipelines & Transmission lines where, not only does damage increase while waiting for responses but, the ability to track saboteurs also decreases exponentially as described in the beginning of this article.

Speed counts. Getting there is not as important as getting there in time.