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flying the approach from the left seat; aNASA safety pilot occupied the rightseat. The two views of a synthetic worldwere presented on a liquid crystal dis-play mounted in front of the instrumentpanel. This research LCD could be re-

moved in a few seconds in case of anemergency.

In addition, the highway-in-the-skyguidance on the head-down displayshowed the pilot curved approaches with180-deg. turns modeled on geometry foroperations into Reno/Tahoe Internation-al Airportwhich was chosen becausethese types of race-track approaches areneeded to avoid high terrain.

On the test I observed, USAF Maj.William Spangenthal, chief of the future

concepts section at Air Mobility Com-mand headquarters, flew a half-dozencurved approaches into Runway 04 at

Wallops; some of them came in from theleft of final and some from the right.

Spangenthal intercepted the highway-in-the-sky tunnel (a row of boxes show-ing the pilot where to fly) using an over-the-ground-track indicator, which

Boeing pilots callthe noodle. Itprojects the air-crafts track for thenext 30 sec. Byturning the aircraft

until the noodle isaimed into themouth of the tun-nel, the pilot com-pletes the inter-cept.

Even though hedid not have theadvantage of asimulator sessionor any instructionprior to trying thisprocedure, Span-

genthalan expe-rienced militarytransport piloteasily interceptedthe tunnel usingthis method.

Once the tunnel is captured, the pilotcan monitor his position with an outerand inner series of aiming boxes (see cov-er) that show him where the cues expectthe aircraft to be in 5.5 sec. The innerbox (marked with four white angles atthe corners) was added as a fine-tun-ing aiming feature after pilots request-ed it in earlier evaluations.

The five-sided outer boxes are in theshape of a doghouse with a roof apexthat helps pilots keep track of lateralalignment in the tunnel. If the flightpath predictor (the circle with wings rep-resenting where the airplane will be in5.5 sec.) is in the center of the inner box,the aircraft can stray 250 ft. left or rightor 150 ft. up or down in flight before ex-iting the outer wall of the tunnel.

Barrows of Nav3D says these trials areshowing that pilots can maintain aircraft

position in the center of the tunnel with-in 30 ft. vertically and horizontally. Thisis more precise than pilots can usually

ENHANCED & SYNTHETIC VISION

MMW Ready To RollCombining millimeter-wave and Flir imagerycreates new possibilities for enhanced visionDAVID HUGHES/HAMPTON, VA.

illimeter-wave radar com-bined with forward-lookinginfrared imagery is nearlyready for operational use, asshown by approaches flown

to Wallops Flight Facility near here.A NASA Lang-

ley Research Cen-ter 757 testbedfitted with millime-ter-wave (MMW)and Flir sensors by

BAE Systems flewfrom Langley AFBhere for a series ofdemons trat ionflights to Wallops.Air Force, FAAand airline pilotswere able to seewhat its like to flyapproaches usingenhanced and syn-thetic vision. Thiscombined version

of enhanced visionmelds Flir imageryand MMW returnsinto one picture ina head-up display.In addition, syn-thetic vision is provided in a head-downdisplay with a computer-generated 3Dview of the terrain ahead. This is overlaidwith highway-in-the-sky guidance (seecover).

ThisAviation Week & Space Technol-ogy pilot watched the approaches on re-peater displays in the back of the 757,along with engineers and pilots fromHoneywell, BAE and the U.S. Air Force.

The synthetic vision capability was pro-vided by Nav3D. The small, Silicon Val-ley-based consulting company, led byCEO and co-founder Andrew K. Bar-rows, doesnt plan to create its ownavionics products. Ratheras in thiscase, where its subcontracted to BAESystemsNav3D plans to focus on theresearch and development phase of cre-ating advanced avionics systems.

For the NASA tests, Nav3D provid-

ed the synthetic vision view of the out-side world in both a primary flight anda navigation display shown to the pilot

M

NASA 757 HUD displays BAE Systemsenhanced visionmillimeter-wave radarreturns fused with shortwave infraredimageryon approach to Runway 04 atWallops Flight Facility. Green scintillation isradar reflection; object on threshold is aparked van to show MMW sensor capability.

BAESYSTEMS


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fly using glideslope and localizer needleson conventional ILS approaches.

Once the 757 was aligned on final ap-proach to Wallops Runway 04, Spangen-thal then had to transition from the head-down synthetic vision view to the head-upfused image derived from millimeter-wave imagery and Flir. This was possi-ble starting as high as 1,000 ft. using the

Flir; but at lower altitudes, closer to 500ft., the MMW sensor came into rangeand started showing a more well-defined

outline of the runway. Spangenthal usu-ally completed the transition to the head-up display by this altitude and followed

the fused image down to 200 ft., wherehe executed a missed approach.

Because it was a clear day, a card wasplaced in front of the HUD so Spangen-thal could not see through it to the out-side world and visually spot the runway.Thus, he saw only the fused imageryfrom the sensors. This demonstrationused a Rockwell Collins HGS-4000HUD.

BAE Systems installed both a Flir Sys-tems Inc. short-wave infrared camera anda BAE long-wave camera. The short-

wave (0.9 to 1.5 microns) camera is de-signed to pick up high-intensity runwaylighting; the long-wave one (8-12 mi-crons) provides thermal images fartheraway from the visible spectrum. So a va-riety of fused images was presented, withmillimeter-wave radar images being com-bined with either short-wave or long-waveFlir, or both.

From my seat in the back of the air-craft, it was difficult to distinguish thebenefits of the various sensor combina-tions. And, in fact, BAE plans to workwith the Air Force Research Laborato-ry on a flight test project to gather pi-lot impressions of different sensor dis-plays in actual low-visibility weatherconditions.

But the millimeter-wave returns werenoticeable as we descended below 500ft., because this imagery scintillates inthe displayclearly outlining the run-way. In addition, NASA had a van parkednear a taxiway or, in some cases, on thethreshold during our approaches to showoff the MMW radars ability to highlighthazardous objects. Without training, a

pilot could confuse the bright scintilla-tion at the end of the runway; however,

once he knows what to look for, its easyto spot the van.

The point of all this is that whentheres dense, large-droplet fog, it prob-

ably wont be possible for a pilot to seethe runway with Flir imagery. But MMWradar can penetrate fogwhich is whyit would be desirable as an add-on to Flir.Moreover, the radar works well in dustyconditions such as those found in the

Middle East, according to MichaelFranklin, the systems architect on thisBAE project.

Forward-looking infrared sensors arealready operational as enhanced visionsystems, offering pilots of some of thelatest Gulfstream business jets a betterview of the runway and surrounding ter-rain at night and in certain types of low-visibility conditions. Gulfstreams sys-tem uses a Kollsman Flir camera. ButMMW radar has not shown up yet oncorporate, military or commercial jets.

Now, after 11 years of development,

BAE Systems says its W-band, 94-GHz.radar is ready to become a product as

soon as a launch customer is identified.A military buyer will probably come first,and BAE is aiming for both fixed- androtary-wing applications, according to

Thomas Herring,vice president andgeneral managerof the companysIntegrated Sys-

tems unit.The experimen-

tal MMW antennaused on the NASA757 tests measures24 X 10 X 9 in.The transmit-and-receive array wasscanned mechani-cally to 15 deg.The Cassegrainantenna design isadopted from

optical telescopetechnology toachieve the desiredfocus in a smallerunit. The radarsystem weighsabout 100 lb.; if its

light enough for helicopters, it should belight enough for small jets, according toBAE.

The company, along with the U.S. AirMobility Command and the Air ForceResearch Laboratory, plans to begin

flight tests on a C-130 next yearwith a millimeter-wave system.This will be part of the AFRLsAutonomous Approach andLanding Capability demonstra-tion. In next years trials, theplan is to test the avionics in ac-tual low-visibility and fog con-ditions.

At NASA Langley, the mil-limeter-wave/synthetic visiondemonstration flightscalledthe Follow-on Radar, Enhanced

and Synthetic Vision System IntegratedTechnology Evaluation, or Foresite,testsconclude a six-year aviation safe-ty and security program. This effort wasdesigned to study techniques that couldreduce controlled flight into terrain andother causes of fatal accidents.

George B. Finelli, director of the pro-gram for NASA, says the work has beenproductive, but more research is neededon synthetic and enhanced vision. Al-though hes not yet certain what projectsmight follow based on the next budgetsubmission, he says the technology re-

mains a high priority with NASA, theFAA and industry. c

NAV3D

CORP.

Top-down view of the curved approach intoWallops shows the path of the highway-in-the-sky tunnel over the ground. Thisapproach models one used for operationsinto Reno/Tahoe International Airport.

MMW radartechnology is

now ready for use infixed- and rotary-wing

military aircraft

Posted from Aviation Week, November 28, 2005, copyright by The McGraw-Hill Companies, Inc. with all rights reserved.

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About the Cover

This synthetic-vision view with highway-

in-the-sky guidance allowed pilots

on a NASA Boeing 757 to fly curved

approaches into NASAs Wallops Flight

Facility during recent demonstrations.

The software was developed by Nav3D

Corp. of San Carlos, Calif., a consulting

company formed by Ph.D. graduates

of Stanford Universitys GPS laboratory.

The display enhances situational aware-

ness while allowing a pilot to fly to a

point where he can pick up BAE Systems

enhanced-vision sensor imagery of the

runway for guidance on final approach.

Synthetic and enhanced vision systems

are in flight test and limited operationaluse. Nav3D image.

FOR FURTHER INFORMATION, CONTACT:

BAE SystemsP.O. Box 56901

Los Angeles, CA 90056Telephone [email protected]

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