The following is an html version of the letter on one side of the handout. On the other side of the handout is a comic strip entitled "Tom's Contrails." For more background, see "I'd rather RAAS."

April 16, 2002

Dear 2002 Ohio Airports Conference attendee,

Safety and utility in aviation are built upon the precept of backup systems being immediately available. However, over approximately the last 5 years, due to an effort to reduce clutter on Terminal Procedure charts, many airports in Ohio are now without a set of published alternate minima based upon a different airport's barometric altimeter setting. This has serious implications. An unplanned outage of an automated weather system (i.e. AWOS/ASOS) could leave the pilot with all instrument approach procedures into their intended destination becoming instantly NOT AUTHORIZED!

Before this change, it used to be that there were two sets of minimum altitudes upon which pilots could base their safe descent upon. The lowest altitude was predicated upon receipt of a local altimeter setting. The alternate, somewhat higher minimum altitude, was based upon a Remote Altimeter Setting Source (RASS). Those alternate minima were carefully calculated, based upon formula found in Chapter 3 "Takeoff and Landing Minimums" of FAA Order 8260.3 "United States Standard for Terminal Instrument Procedures (TERPS). It is this alternate set of minima that has imperceptibly disappeared from instrument approach charts over the past 5 years. This "clutter" reduction was well intended, but it can have serious ramifications when an AWOS or ASOS fails and the weather requires an instrument letdown.

In an analysis completed by CFW last Fall, it was found that Ohio has 300 Terminal Procedures into 109 public use airports. This situation affects nearly 50% of these 109 airports! (see airport listing at bottom*)

We feel it is absolutely critical for pilots and airport managers to be aware of this situation, and we strongly encourage airport managers to request the reestablishment of RASS minima on Terminal Procedures into their airports. The contact person at the FAA is...

Roger L. Lucas (AVN-170H)
The Chicago Flight Procedures Office
FAA Great Lakes Regional Office
2300 East Devon Ave.
Chicago, IL 60018
Email: roger.l.lucas@faa.gov
Telephone 847-294-7254 Voice, 847-294-7124 Fax

Further info, as well as background and links pertaining to this situation, can be accessed on the internet at http://home.columbus.rr.com/lusch/raasletter.html.

Sincerely,

Thomas G. Lusch <tomlusch@yahoo.com>
Board Member, CFW & Aviation Safety Counselor, CMH FSDO

* 0G6 12G 16G 17G 2H2 3G4 4G5 4I3 56D 5G7 6G5 7I7 8G6 AKR AMT AOH AXV BJJ BKL CDI DFI EOP FDY FZI HAO HZY I10 I23 I40 I68 I69 I78 I86 I95 ISZ LHQ LPR LUK MFD MGY MNN MWO HOC OSU OWX PCW PHD PMH TDZ TZR UNI UYF VTA ZZV