UAS GCS Human Factors Issue ASCI 638 - 2.6

Predator RQ-1

The RQ-1 Predator is a long-endurance, medium-altitude UAS for surveillance and reconnaissance missions and interdiction. Imagery is provided from synthetic aperture radar, video cameras and a forward-looking infrared (FLIR) can be sent real-time to the front-line soldier, operational commandeer or worldwide via satellite communications. It can be armed with AGM-114 Hellfire missiles.  The ground control station (GCS) is a single 30 foot trailer, containing pilot and payload operator consoles, three Boeing data exploitation and mission planning consoles and two synthetic aperture rater workstations. It is launched with direct line-of-sight control from a semi-improved surface. Line-of-sight data link or satellite links produce continuous video for the operators and all controls are commanded through those communication channels (Predator RQ-1, n.d.).

One human factors issues that lead to an accident was the design of a control lever made it easy to create a mishap. The GCS has two operators who sit at identical consoles. One operator is the pilot and the other is the payload operator. When configured for the pilot the condition lever will start or stop fuel flow and can feather the propeller to reduce drag. When configured for the payload operator the same condition lever will operate the iris on the camera. Per the checklist if control is transferred from one console to the other the condition lever on the payload console must be set to match the pilot console prior to transfer of controls. During a control transfer the checklist was not followed and the condition lever was not matched. Once the transfer of controls was completed the conditions lever which had been set to control the iris was not set to stop fuel flow to the engine, causing the engine to shut down. This was a major contributing factor to a Predator crash in 2016 in Arizona (Carrigan, Long, Cumming & Duffner, n.d.)

This failure mode could be designed out of the system. Something as simple as having two distinct condition levers, one for the iris control and a separate for engine control.  Another would be to prevent or give a warning if pilot control transfer is attempted and the condition lever is not matched between the two control consoles (Carrigan, Long, Cumming & Duffner, n.d.). “While some would advocate for more training to address this problem, humans are imperfect systems, and it is important to design for an operator that may make mistakes” (Carrigan, Long, Cumming & Duffner, n.d.).

Human factors in cockpit design occurs both in unmanned and manned aircraft systems. The cockpit needs to be designed in such as way as to allow the pilot to be efficient and comfortable as possible.  “One of the first formal human factors studies was carried out by Fitts and Jones in 1947 to analyze pilot experiences with display readings” (Flying Towards the Future).  In the late 1970s cockpits had an excess of 100 individual components the pilots were required to monitor and manage, the technology at the time only allowed for a gauge to display one piece of information (Salas, E., Maurino, 2010).

Another human factors issue is the limited field of view for the Predator operator. The original design of the GCS gave approximately a 30-degree field of view from the nose camera. It was stated that it is similar to “driving your care with paper towel tubes over your eyes” (Shiner, 2001). This is shown on one screen for the pilot overlayed with information such as transponder code, airspeed and

Original GCS Cockpit   (It's Better to Share, 2011)

altitude. A second screen providing data such as a map with a symbol of the aircraft and the corridor for its’ route of flight. This limited field of view, and the lack of vestibular and proprioceptive cues, means the pilots rely on visual cues to fly, such as when the runway fills the bottom third of the screen the nose is raised to flare prior to touchdown.

Raytheon designed a new cockpit for the GCS that now has three wide screens and a 270-degree field of view with some synthetic data overlayed. This allows for a large increase in the pilot’s situational awareness. This improved display along with more ergonomic controls, more comfortable

Advanced GCS (Pocock, 2007)

and adjustable seat as well as new interfaces increases the comfort of the pilot as well as their situational awareness (Pocock, 2007).

Limited field of view can occur with manned aircraft as well.  Many military and civilian pilots fly at night under Night Vision Devices (NVD) such as night vision goggles. These goggles limit the field of view to around 40-degrees. The pilot overcomes this limitation by increasing scan rate, looking left and right frequently and not relying on peripheral vision in order to see surroundings.

References

Carrigan, G., Long, D., Cummings, M., & Duffner, J. (n.d.). Human Factors Analysis of Predator B Crash [Scholarly project]. Retrieved January 21, 2018, from https://hal.pratt.duke.edu/sites/hal.pratt.duke.edu/files/u13/Human%20Factors%20Analysis%20of%20Predator%20B%20Crash%20.pdf

Flying Towards the Future: An Overview of Cockpit Technologies (October, 2013). Retrieved January 21, 2018 from http://www.ergonomics.org.uk/flying-towards-the-future/ 

Its Better to Share: Breaking Down UAV GCS Barriers. (2011, October 03). Retrieved January 21, 2018, from https://www.defenseindustrydaily.com/uav-ground-control-solutions-06175/

Pocock, C. (2007, June 16). New UAV Control System May Cut Predator Losses. Retrieved January 21, 2018, from https://www.ainonline.com/aviation-news/defense/2007-06-16/new-uav-control-system-may-cut-predator-losses

Predator RQ-1 / MQ-1 / MQ-9 Reaper UAV. (n.d.). Retrieved January 21, 2018, from http://www.airforce-technology.com/projects/predator-uav/

Salas, E., Maurino, D. E. (2010). Human factors in aviation (2nd ed.). Amsterdam: Academic

            Press/Elsevier

Shiner, L. (2001, April 30). Predator: First Watch. Retrieved January 21, 2018, from https://www.airspacemag.com/military-aviation/predator-first-watch-2096836/?all