A small unmanned air systems(UAS) could perform commercial flights in most US airspace at up to 500ft in daylight as long as it remains within eyesight of an observer or an operator who has passed an aeronautical knowledge test.

That is the long-awaited regulatory framework finally proposed by the US Federal Aviation Administration on 15 February after more than eight years of deliberation and a failed legal challenge last year to its authority over small UAS.

Despite reports suggesting the FAA would require a pilot’s license to operate a small UAS – defined as weighing up to 25kg (55lb) – the notice of proposed rulemaking would require that an operator only pass an FAA-administered knowledge test.

Small UAS also would not face an airworthiness certification process equivalent to a manned aircraft, although the vehicle must be made available to the FAA for inspection if asked.

At the same time, the FAA’s proposed rules for small UAS stop short of satisfying a rapidly proliferating community of aspiring commercial drone operators.

The proposal would ban the operation of small UAS beyond visual range of the operator and over the heads of other people, negating attempts by companies such as Amazon to launch drone delivery services in big cities.

All sides of the small UAS debate, however, are glad to see the FAA publish the proposal after years of delays. The National Business Aviation Association (NBAA) calls the new rulemaking a “good first step”. But the debate over how small UAS get integrated in the national airspace has only just begun.

By publishing the notice of proposed rulemaking, the FAA unleashes a potentially overwhelming 60-day comment period. A similar comment period two years ago over a minor rewrite of guidelines for operating drones as a hobby generated more than 100,000 submissions, and FAA officials expect the commercial rules to generate even more discussion.

The policy debate could drag on for months or years before a final rule is published. Congress gave the FAA a year-end deadline for approving the regulations. However, last May, an FAA official noted that it takes an average of several years to process a controversial rulemaking – and the small UAS rules fits the definition of controversial. More recently, the US Government Accountability Office – the auditing arm of Congress – estimated that passage of a final rule could take two to three years.

For his part, FAA administrator Michael Huerta prefers to be optimistic about the timeline. The NPRM provides a “very comprehensive” framework that should make it easier for the FAA to analyse, he says, and “move this rulemaking as expeditiously as possible”.

The FAA proposal comes after several countries, including Australia, Canada and the United Kingdom, have already implemented regulations that allow small UAS to operate commercially. Other countries, such as India, have banned operating drones completely.

In the USA, there are still many questions about the details and the pace of opening up airspace to UAS for commercial purposes. The FAA rulemaking, for example, asks for feedback on whether the agency should establish a separate category for UAS weighing less than 2.2kg with fewer operating restrictions.

Operating UAVs weighing more than 25kg – or at night for any size UAS – remains a distant goal, requiring years of further research. The FAA’s UAS roadmap released a year ago envisions a very gradual transition for large UAVs paced by the development of sense and avoid and command and control technology.

The first step involves establishing a ground-based sense-and-avoid system, a technology already in operation by the US Army. That system solves the problem of deconflicting UAVs with manned aircraft traffic while on descent. That is a phase of flight for the UAS where currently available radars have trouble detecting potential collision threats against the clutter of the ground.

In the very far-term, an airborne-based sense and avoid system is still needed to integrate all sizes of UAS into the airspace on a routine basis.

The proposed rulemaking for small UAS marks “another step in a process that has a lot of components” Huerta says. “This is not the final word on full scope of UAS operations.”

Source: FlightGlobal.com