Choices for DRVSM

The article "Countdown to DRVSM" (March 2003, page 42) was well written by Adrian Gerold. But it omitted some important information in the sidebar titled "DRVSM Flight Tests." In paragraph four, the article states that the "aircraft owner must contract ARINC to install a GMU (GPS monitoring unit) on the aircraft and take on board an engineer." This is not the only choice the owner has.

CSSI Inc. has the same capability that ARINC has. In fact, it can also train the operators to do the monitoring themselves, something ARINC will not do. Your readers should know that they have choices.

Joe Williams
Washington, D.C.

Ridiculous Technology

I was troubled by the article in the October 2001 issue (page 28) titled "Memphis: The Future of Airport Surface Management," which I read in the archive section of your Web site. It is hard to understand how multilateration will be cost- and performance- competitive with GPS and its augmentations. As far as surveillance goes, Mode S is plagued with problems on the airport surface. ASDE (airport surface detection equipment) does not even interface with Mode S.

This is the most ridiculous assembly of expensive incompatible technology I have seen. GPS is mentioned only as a "lip service" gesture just to keep GPS advocates happy, so they will not take aim at this abomination of technology and kill it before it takes another breath.

When an ATC (air traffic control) advancement is measured by controllers getting color raster displays, it makes me wonder what this industry is all about. This seems to be another attempt to confuse and mislead a troubled industry to benefit some radar and Mode S companies and to keep some bureaucrats employed.

Why don’t you present the work of NASA and others? These technologies have a future and are deployable at large and small airports alike.

H. Robert Pilley
President and CEO
Pilley Labs
Hillsboro, N.H.

Pilley holds nine U.S. patents on airport control and management using GPS.

I’m With Your, Too, Pete

Pete Gillies’ letter in the Feedback section of the March issue (page 8–responding to the System Design column in the October 2002 issue [page 43]) is right on the mark.

I am a pilot and have been around long enough to know the tremendous strides made by an avionics industry that understood the safety and pilot workload aspects of operating an airplane. I go back to pre-digital ADF tuning and four-course ranges.

Now the industry seems to have been taken over by computer-nerd button pushers with no idea of what’s going on. Their only objective is to cram as many useless functions as possible into equipment.

I have a dandy GPS that will compute true airspeed. However, I can compute airspeed in a quarter of the time with a 30-year old wizz wheel without taking a chance of disturbing a navigation function.

I have hit the wrong button or sequence on another piece of gear and blew away the antenna connection. I do not have the time or inclination to troubleshoot these idiot boxes in flight.

I also have a multifunction display, which replaces my radar scope. It used to take one click to turn the radar on; now it takes about eight.

Is this progress? More heads-down time equates to less safety.

I recently browsed an avionics suite that required an alpha-numeric function keyboard. A rep came over and told me how grand this was. I asked him if he was a pilot. He said, no. I suggested he try playing this game in the black of the night, arriving or departing New York City, with constant air traffic control changes and a thunderstorm or two to spice things up.

A pilot friend recently confided that he was concerned about a job interview that included a simulator ride. He allowed that his typing skills had improved, but his flying skills were a bit rusty.

Frank Sinnott
Raleigh, N.C.

Digital Acronym Lexicon

I enjoyed seeing the "Aerospace Acronym, Initialism and Abbreviation Guide" published in your December issue and thought your readers might appreciate having a similar digital version that I have been working on for several years. My lexicon is specialized toward avionics terminology and covers some 800 acronyms, abbreviations, initialisms and shortcuts that are commonly used in commercial aviation.

While your published document is a great boon for this industry, there are some advantages to having a document in electronic form: the ability to search for terms, add new terms, link to Web sites and forward the document to others are some obvious examples. My document is in MS Word format (24 pages, 12-point type, 150 kilobytes) with bookmarks for each letter of the alphabet. It is also searchable using standard word processing tools. There are Web links to most non-commercial organizations (e.g. ANSI, ARINC).

I am offering this document free of charge for a limited time to Avionics Magazine readers via e-mail. My only requirement is that anyone who requests it must leave my copyright information intact and provide appropriate credit when forwarding it to someone else. Simply send an e-mail with the subject "Acronyms" to: [email protected].

Jim Veihdeffer
Words in Action
Tempe, Ariz.

Added Acronyms

Regarding your acronym guide in the December 2002 issue, I note that you listed RTCA (Radio Technical Commission for Aeronautics). Here are items from my personal list, which often are used within the RTCA community. By the way, although you included GDAP (growing danger of acronym proliferation), you didn’t list GROAN (Get Rid of AcroNyms).

  • 2/3m95% less than 2 to 3 meters 95% of the time
  • 24/7 24 hours per day, 7 days per week
  • APDU application protocol data unit
  • ASE application service element
  • ASN.1 abstract syntax notation, version one
  • AWW severe weather forecast alert
  • BMS bit map section
  • CAS controlled access service
  • CDMA carrier division multiple access
  • CG Coast Guard
  • CGSIC Civil GPS Service Interface Committee
  • CRLF carriage return line feed
  • DF direction finding
  • EC European Commission
  • EOW end of week (rollover 1,024 weeks from GPS initial start)
  • FAI Federation Aeronautique Internationale
  • FFSC Free Flight Steering Committee
  • FFDCC Future Flight Data Collection Committee
  • FISDL flight information service data link
  • FQ03 First Quarter, 2003
  • FR flight recorder
  • fpm feet per minute
  • fps feet per second
  • GDS grid description section
  • GRIB gridded binary
  • IAIN International Association of Institutes of Navigation
  • ISU interference suppression unit
  • ITRF international terrain reference frame
  • L51176.45MHz (adopted civil safety-of-life signal)
  • LIFR low instrument flight rule
  • MIDS multifunction information distribution system
  • mph miles per hour
  • mpm miles per minute
  • mps miles per second
  • MNG multiple-image network graphics
  • MTSAT Asian WAAS equivalent
  • MVFR marginal visual flight rules
  • NCEP National Centers for Environmental Prediction
  • NDGPS national differential GPS
  • NGS National Geodetic Survey
  • NLDN National Lightning Detection Network
  • NSME network system management entity
  • OAS open access service
  • ns nanosecond (one billionth of a second)
  • OPCON operational control
  • OpEval operational evaluation
  • PDS product definition section
  • PMC program management committee
  • PNG portable network graphics
  • PPS precise positioning service (using P[Y] code on both L1 and L2)
  • R/C rate of climb/descent
  • RUC rapid update cycle
  • SPI subsequent protocol identifier
  • SSA Soaring Society of America
  • SVN satellite vehicle number
  • TF4 Task Force 4
  • TIFF tagged image file format
  • TMA terminal maneuvering area
  • USNO U.S. Naval Observatory
  • VIP video integrated processor
  • VMEVDL management entity
  • WRC World Radio Conference
  • Y2K year 2000

Thanks again for a fine piece of work.

Bernald S. Smith
FAI/SSA RTCA Representative

Still More Acronyms

A timely article on acronyms, initialisms and abbreviations. It was good and almost complete. However, it lacked the following:

  • DVOR–Doppler VOR,
  • CVOR–conventional VOR and
  • SLS–satellite landing system

What About Anti-Fuse Parts?

Your System Design column in the February 2003 issue (page 42) confirmed my long held suspicion of EEPROMs (electrically erasable programmable read-only memory) being unreliable for storing data long term. But what about anti-fuse technology?

Don Ausherman
Design Engineer
Lee Air Inc.
Wichita, Kan.


I am not sure about anti-fuse parts, as I don’t work with them. My biggest worry is the logic implemented with this technology, which can lead to bizarre and unpredictable results during failure. A new trend is surfacing: limited-life parts made in small geometries. These exhibit faults within five years due to electrochemical interactions at such fine line widths, but are being used in cell phones and other gear with a predicted short user lifespan. Now that’s truly scary.
–Walter Shawlee 2

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