The ROTO system provided guidance that resulted in mean ROT values essentially the same as those for current clear-weather operations and standard deviation ROT values a factor of 1.5 to 2.0 less (depending on exit comparison). Assuming the pilots can follow the guidance in low visibility conditions, these ROT values imply that clear-weather runway capacity could be maintained in low visibility conditions. All the pilots liked the system and found the guidance easy to follow after a couple of training runs. In general, the pilots were able to control the aircraft ground speed along the runway to within 10 knots of commanded ground speed from the ROTO guidance.

Description and flight test of a rollout and turnoff (ROTO) head-up display (HUD) guidance system

The reduction of runway occupancy time through the use of high-speed exits is one of the research activites carried out to improve the operational use of runways. Proper hardware and software technologies are being developed to minimize runway occupancy time per landing aircraft in future air traffic control environments. On the software side, a probabilistic computer model is being used to define exit velocities, exit locations, and turnoff path profiles under automated landing, rollout, and high-speed turnoffs using embedded magnetic cable sensors. However, the computer model does not determine how to combine these exit locations into a practical number of turnoffs that satisfy various aircraft mixes. The focus of this paper is on clustering these exit locations into a minimum number without cost-burdening any one class and violating the objective of minimizing the total runway occupancy time of landing aircraft in a real airport environment.

Optimal location of high-speed runway exits using automated landing, rollout, and turnoff

This report describes the software products, system architectures and operational procedures developed by Lockheed-Martin in support of the Roll-Out and Turn-Off (ROTO) sub-element of the Low Visibility Landing and Surface Operations (LVLASO) program at the NASA Langley Research Center. The ROTO portion of this program focuses on developing technologies that aid pilots in the task of managing the deceleration of an aircraft to a pre-selected exit taxiway. This report focuses on software that produces a system of redundant deceleration cues for a pilot during the landing roll-out, and presents these cues on a head up display (HUD). The software also produces symbology for aircraft operational phases involving cruise flight, approach, takeoff, and go-around. The algorithms and data sources used to compute the deceleration guidance and generate the displays are discussed. Examples of the display formats and symbology options are presented. Logic diagrams describing the design of the ROTO software module are also given.

/pdf/roll-out-and-turn-off-display-software-for-integrated-33ujuwxl6f.pdf

Roll-Out and Turn-Off Display Software for Integrated Display System

MLS/INS Terminal Area Navigation

This report examines a rollout and turnoff (ROTO) system for reducing the runway occupancy time for transport aircraft in low-visibility weather. Simulator runs were made to evaluate the system that includes a head-up display (HUD) to show the pilot a graphical overlay of the runway along with guidance and steering information to a chosen exit. Fourteen pilots (airline, corporate jet, and research pilots) collectively flew a total of 560 rollout and turnoff runs using all eight runways at Hartsfield Atlanta International Airport. The runs consisted of 280 runs for each of two runway visual ranges (RVRs) (300 and 1200 ft). For each visual range, half the runs were conducted with the HUD information and half without. For the runs conducted with the HUD information, the runway occupancy times were lower and more consistent. The effect was more pronounced as visibility decreased. For the 1200-ft visibility, the runway occupancy times were 13% lower with HUD information (46.1 versus 52.8 sec). Similarly, for the 300-ft visibility, the times were 28% lower (45.4 versus 63.0 sec). Also, for the runs with HUD information, 78% (RVR 1200) and 75% (RVR 300) had runway occupancy times less than 50 sec, versus 41 and 20%, respectively, without HUD information.

/pdf/rollout-and-turnoff-roto-guidance-and-information-displays-56rjwhb22z.pdf

Rollout and Turnoff (ROTO) Guidance and Information Displays: Effect on Runway Occupancy Time in Simulated Low-Visibility Landings

This paper describes the navigation and guidance system developed for the TCV B-737, a Langley Field NASA research aircraft, and presents the results of an evaluation during final approach, landing, rollout and turnoff obtained through a nonlinear digital simulation. A Kalman filter (implemented in square root form) and a third order complementary filter were developed and compared for navigation. The Microwave Landing Systems (MLS) is used for all phases of the flight for navigation and guidance. In addition, for rollout and turnoff, a three coil sensor which detects the magnetic field induced by a buried wire in the runway (magnetic leader cable) is used. The outputs of the sensor are processed into measurements of position and heading deviation from the wire. The results show the concept to be both feasible and practical for commercial type aircraft terminal area control.

R. M. Hueschen

Papers

Guidance and navigation for automatic landing, rollout, and turnoff using MLS and magnetic cable sensors