Frontiers of Engineering Reports on Leading-Edge Engineering from the 2010 Symposium (2011) / Chapter Skim
Currently Skimming:
Certifiable Autonomous Flight Management for Unmanned Aircraft Systems--Ella M. Atkins
Certifiable Autonomous Flight Management for Unmanned Aircraft Systems--Ella M. Atkins
Pages 111-124
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 111... ...
will achieve unprecedented levels of throughput1 and safety by judiciously integrating human supervisors with automation aids. NextGen designers have focused their attention mostly on commercial transport operations, and few standards have been proposed for the burgeoning number of unmanned aircraft systems (UAS)
|
From page 112... ...
Second, although transport aircraft typically fly direct routes to deliver their payloads, surveillance aircraft are capable of dynamically re-planning their flight trajectories in response to the evolving mission or to observed data (e.g., the detection of a target to be tracked)
|
From page 113... ...
ADDRESSING SAFETY CHALLENGES In the discussion that follows, we look first at the problem of certifiable autonomous UAS flights in the context of current flight and air traffic management (ATM) technologies, which are primarily designed to ensure safe air transporta tion with an onboard flight crew.
|
From page 114... ...
To operate efficiently in controlled NextGen airspace, all aircraft will be equipped with an onboard flight management system (FMS) that replicates current functionality, including precise following of the approved flight plan, system monitoring, communication, and pilot interfaces (Fishbein, 1995; Liden, 1994)
|
From page 115... ...
In this section, we focus on the "surveillance" missions that distinguish UAS -- particularly small unmanned aircraft that must operate at low cost in sparsely populated airspace -- from traditional transport operations. Traditional Transport Operations Traditional transport aircraft have a single goal -- to fly a human or cargo payload safely from an origin to a destination airport with minimal cost to the airline.
|
From page 116... ...
UAS missions also will overfly populated areas for a variety of purposes, such as monitoring traffic, collecting atmospheric data over urban centers, and inspecting sites of interest. Even small unmanned aircraft have the capacity to provide support for communication, courier services, and so on.4 Unmanned aircraft can work in formations that can be modeled and directed as a single entity by air traffic controllers.
|
From page 117... ...
Source: Atkins et al., 2009. EXTENDING THE FLIGHT ENvELOPE TO MINIMIZE THE RISk OF LOSS-OF-CONTROL Loss-of-control, the most frequent cause of aviation accidents for all vehicle classes, occurs when an aircraft exits its nominal flight envelope making it impos sible to follow its desired flight trajectory (kwatny et al., 2009)
|
From page 118... ...
Once the envelope has been identified, a landing flight plan guaranteed to be feasible under the condition of the control surface jam can be automatically generated. Figure 4 illustrates the emergency flight management sequence of discovering the degraded flight envelope, selecting a nearby landing site, and constructing a feasible flight plan to that site.
|
From page 119... ...
Trim State Envelope Exploration Discovery Trajectory Runways Range Constraints Landing Site Trim States & Selection Transitions Landing Runway Landing Real-time Flight Plan Flight Planner FIGURE 4 Simplified version of an emergency flight-planning sequence for a jet with degraded performance.
|
From page 120... ...
Figure 6 illustrates the feasible landing trajectories for Flight 1549 automatically generated in less than one second by our pre-existing engine-out flight planner adapted to Airbus A320 glide and turn capabilities. Notably, runway 31 was reach FIGURE 5 Post-landing photo of US Airways Flight 1549 in the Hudson River (http:// www.wired.com/images_blogs/autopia/2010/01/us_airways_1_cropped.jpg)
|
From page 121... ...
In short, this simple, provably correct "glide to landing" planning tool represents a substantial, technologically sound improvement over the level of autonomous emergency flight management available today and is a step toward the more ambitious goal of fully autonomous flight management. CERTIFICATION OF FULLY AUTONOMOUS OPERATION Every year the FAA is asked to certify a wide variety of unmanned aircraft for flight in the NAS.
|
From page 122... ...
Addressing Rigidity in Flight Management Systems The remaining vulnerability of a fully autonomous UAS FMS is its potential rigidity, which could lead to an improper response in a truly unanticipated situ ation. The default method for managing this vulnerability has been to insert a human pilot into the aircraft control loop.
|
From page 123... ...
2010b. Emergency Landing Automation Aids: An Evaluation Inspired by US Airways Flight 1549.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.