Safety Board Probes a Manned/Unmanned NAS

Air Safety Week, May 5, 2008

Unmanned Aerial Vehicles (UAVs), or Unmanned Aerial Systems (UAS) as the Pentagon prefers to call them, were developed to be three-dimensional creatures, that is military machines designed to conduct "3-D" dull, dirty and dangerous missions deemed too hazardous for humans. However, with increasing interest and operation of drones for public purposes and commercial tasks, UAS are now entering a fourth dimension, that being of a 'domestic' nature.

But the snail's pace in promulgating regulations that would allow for regular flights of military, public-use and civil UAS in the National Airspace System (NAS) is holding back the potential of the unmanned technology and the number of non-military missions envisioned by UAS proponents. And Federal Aviation Administration (FAA) officials appear to be in no rush to establish "rules of the road" for unmanned aircraft operations in U.S. civil airspace.

To make matters worse, the most visible use of non-military drones within U.S. borders was marred by a crash two years ago that raised serious concerns over what is needed before pilotless planes are allowed to operate in U.S. airspace over both populated and rural areas.

Simply stated, an unmanned aircraft is a device that flies with no onboard pilot. UAs can either be remotely controlled from the ground by an operator or preprogrammed to conduct the entire flight without intervention.

Unmanned aircraft come in all shapes and sizes. They range in wingspan from six inches to 246 feet, and can weigh as little as a few ounces or as much as 100,000 pounds. Some fly no higher than rooftops, while others fly well above piloted aircraft altitudes. Today, according to the FAA, more than 50 manufacturers offer nearly 150 UAS products, with many others poised to enter the commercial marketplace.

The one thing they have in common is that their numbers and uses are growing dramatically and "regulatory standards need to be developed to enable current technology for UA to comply with Federal regulations," the FAA believes.

The National Transportation Safety Board (NTSB) held a two-day forum on the safety of unmanned aerial systems April 29-30 in the NTSB Board Room and Conference Center in Washington, DC. The forum included representatives from the military, industry, the FAA, and government agencies involved in UAS operations.

The forum provided an opportunity for the Safety Board and interested parties to discuss the safety implications presented by the growing use of UAS in the NAS. Issues addressed included: regulatory standards; integration within the NAS; perspectives of current UAS operators; design, certification and airworthiness; human factors; and, future UAS applications.

While military UAS fly at will above overseas combat zones and in controlled military airspace domestically, they are only allowed to fly on a case-by-case basis in non-restricted airspace, the best example of which is the U.S. Customs and Border Protection's (CBP) use of drones for spotting illegal border crossers and drug smugglers.

CBP operate MQ-9 Predator B UAS in Arizona to monitor the US/Mexico border and will soon stand up a second Predator base in North Dakota to keep tabs on the border with Canada. The law enforcement agency hopes to acquire two dozen Predator Bs for overland and maritime interdiction missions.

It is also developing a capability in which Predator Bs and support equipment would be loaded onto U.S. Coast Guard C-130s to handle catastrophic natural disasters and/or monitor major international sports events. The quick- reaction detail would be pre-authorized to fly in civil airspace.

The forum is a result of the Safety Board's investigation of a CBP Predator B crash near Nogales, AZ, on April 25, 2006. The drone, which is about the size of a Cessna 152, crashed within 100 yards of a house in a sparsely populated residential area. Luckily, no one on the ground was injured in the non-fatal mishap, but the remotely piloted 66-foot wingspan drone was substantially damaged.

The Board's October 2007 meeting on this accident resulted in 22 safety recommendations to address perceived deficiencies associated with the civilian use of unmanned aircraft.

"The Nogales accident surfaced a number of important questions that need to be addressed if UAS's are to operate safely in the National Air Space," said Board Member Kitty Higgins, who chaired the forum.

The Predator B flight originated from the Libby Army Airfield (HFU), Sierra Vista, AZ.

The flight was being flown from a ground control station (GCS) located at HFU. The GCS contains two nearly identical consoles, pilot payload operator (PPO)-1, and PPO-2.

During a routine mission, a certified pilot controls the UAV from the PPO-1 console and the camera payload operator (typically a U.S. Border Patrol Agent) controls the camera from PPO-2. The aircraft controls (flaps, stop/feather, throttle, and speed lever) on PPO-1 and PPO-2 are identical. However, when control of the UAV is being accomplished from PPO-1, the controls at PPO-2 are used to control the camera.