AVmail: Mar. 24, 2008


Ric Peri Gets Real About ADS-B

Mr. Peri made some interesting comments (Podcast, Mar. 12).I heard him say that he is solidly behind the technology and compares it to the introduction of VOR technology. I also heard him say that the ADS-B technology has had a great impact on the Alaskan aviation community. Perhaps this forms the foundation of his support for the system.However, I question the validity of the opinion that ADS-B has had a “great impact on the Alaskan aviation community.”While I appreciate that the Capstone Program was the test vehicle for ADS-B and enhanced GPS capability technology, in my opinion ADS-B did not provide the greatest impact on the success of the test. The enhanced GPS capability and onboard avionics displays incorporating position, terrain and weather was the major factor in improved safety due to increased “pilot situational awareness” in an unforgiving environment.The entire Capstone Program was limited to commercial carrier operations in Southeast Alaska (Juneau, Ketchikan, Sitka), with the exception of one test-bed aircraft, a Cessna 172RG at the University of Alaska-Anchorage, Aviation Technology Center.I don’t consider Part 135 and 121 carriers to be the “Alaska aviation community.” GA is the largest part of the Alaska aviation community but all GA was excluded from any portion of the experiment. The test was conducted in a limited area and with a very small part of the Alaska aviation community.The test was lauded as a great success and ADS-B was touted as the best thing since sliced bread, while ignoring the contribution of the enhanced displays and increased situational awareness that was provided by the GPS. So now we have ADS-B being pushed down our throats in the name of enhanced safety for airspace management. The program will be another great success.This is a ruse. ADS-B equipment is currently proposed as mandatory by the FAA for all aircraft wishing to utilize controlled airspace by 2012. The next step is to require ADS-B equipment to utilize any U.S. airspace. The reason will be given as safety and national airspace security to protect us from terrorism.The benefit will be to the FAA and the government, not the aircraft owner and operator.This is just another tool that will be used by the government to limit GA access to airspace and make the cost of aviation in this country higher to the individual operator. NewGen [sic] is another example of this effort.My experience is military aviation (13 years – F-4, F-16, O-2), commercial aviation (20 years, two major carriers; B-727, B-737, B-747, DC-10, A-310) and GA owner/operator. I am not a conspiracy theorist but I can read the handwriting on the wall.Jim Canitz

Diesel Efficiency

Regarding the diesel efficiency blog (AVwebinsider, Mar. 14):In my experience, there are two more reasons why diesels do much better than gasoline. The first is the difficulty a pilot has in achieving those peak efficiency fuel flows with gasoline. It’s easy to be 15 percent off optimum. The second reason is that during warm-up, idle and partial-power operation the diesel is probably running at double or triple the efficiency of gasoline.Dick Van Pelt

Two comments:First, I don’t know exactly how the BSFC calculations work, but your numbers fly in the face of my experience. My 172Ns were burning 8 gph before, and with the 1.7-liter Thielerts we were running in the range of 4.3 gph. Granted we use lower power settings than the average pilot might, but the settings are the same before and after. So, for the same operating regime, I’m burning just over half the fuel. That’s the result of about 1800 hours on two aircraft. One timed out and we just installed a 2.0-liter in its place, and that engine is burning slightly less — 4.1 gph or so — at the same power settings. All the higher math aside, this really shows up at the end of the week. We’re talking 240 gallons of avgas as opposed to 129 or so of cheaper Jet A. I expect that the better torque curve on the diesels has something to do with this as well.On the AD: This was the result of a line not being properly mounted, which was a design flaw. We just did the fix last week, which required replacement of the line and an additional mounting point. Vibration is and always will be an issue with diesels, but that’s something that’s been solved in the field by others. I think this was more an oversight on the part of Thielert rather than an indication of things to come.I’ve had my fun with these engines at times, to be sure, but overall I’m still convinced that they’re a far better deal than the Lycomings.Stan Fetter

AVweb Replies:

Here’s the math: The Twin Star’s 1.7s were burning 5.8 to 5.9 gph (38.86 to 39.53 lbs/hr) at 80 percent. That’s 108 hp. 38.86 divided by 108 is 0.3598 or rounded to 0.36. At the higher number, it rounds to 0.37. Pulled back to 50 percent, the fuel flow is down to about 3.7, which is still around 0.36 to 0.37.

Paul Bertorelli
Editorial Director

Airbus Flap

Regarding the Air Force tanker decision (AVwebFlash, Mar. 2):I wish some newspaper in the Washington area would take a drive thru the employees’ parking lot at the Boeing plant and count the number of Hondas, Toyotas and Kias that are in the parking lot. Don’t ask me to write my congressman … un-American is un-American.C.R. Hutchins

Airline Boarding Research

Jason Steffen has done his best to use science to study aircraft boarding (AVwebFlash, Mar. 13). The usual error of academia is to forget the real world. His system would work well for educated, cooperative adults if they would take direction. How would he take care of families with children or elderly people? The system of boarding from the windows to the aisle would not allow for them and would result in some serious dilemmas.Southwest has the best system I have seen that leads to passenger cooperation: You get on the airplane based on when you get in the boarding pass queue without assigned seating. Assigned seating takes time for most inexperienced passengers. He might look at reversing the system for how passengers disembark. Hand luggage, etc. take time whether you are boarding or leaving the airplane. That is one of the problems the airlines really need to solve. The passenger who thinks they should bring everything into the passenger compartment and stuff it into the overhead leaving no room for other passengers’ belongings are a culprit in the “time to board” problem. Their time is more important than that of others. (My thoughts after watching this interesting human experience since 1953.)Ron Talcott

TSA Disputes Flight School Security Claims

I suspect that I am one of the 8000 “foreign” pilots who obtained an American pilot certificate without a security check (AVwebFlash, Mar. 2). My certificate was issues based on my Canadian documentation under ICAO agreements that recognize and accept pilot qualification standards among ICAO member countries. The issuance of this certificate pre-dates 9/11 and I am not sure what the current practice is.Richard Abbott

Potential Impacts of Climate Change

AVweb wrote (AVwebFlash, Mar. 11),

“Airport runways in coastal areas are in danger of being submerged by rising sea levels and storm surges brought on by global warming …”

This is news? It seems only logical that if coastal areas become flooded, the airports serving those areas will likely be flooded as well.TRB Special Report 290, The Potential Impacts of Climate Change on U.S. Transportation, is short-sighted. It didn’t mention at all that when the next Ice Age comes, many of our airports will also be threatened by advancing glaciers. In fact, the airport I use most often was covered by 5000 feet of ice only 12,000 years ago.Gary Dikkers

English Usage

AVweb wrote (AVwebFlash, Mar. 2),

One of those occupants had also passed by the time of this writing.

Isn’t the simple English word “died” a better choice than a euphemism? Not only is it a euphemism, it’s also ethnic and regional dialect, “passed away” being the standard usage. Yes, I know … the line between English major and grammar scold is a fine one.Farron D. Brougher

Busy Airspace

Your article about biz planes using the same airspace as the airlines make it sound like we are going into the same airports (AVwebFlash, Mar. 18). I think further study would show biz travel going to the reliever airports, not the biggies. We fly in and out of the Chicago area and rarely hear an airliner on frequency.Stu Baxter

Airplane Theft QOTW

Your Questions of the Week (QOTW) frequently offer restrictive or inappropriate choices. This week is no exception (QOTW, Mar. 20). I live in an airpark. My plane is locked inside my hangar, which is part of my house. For this reason, I was forced to choose “I’m not worried about my aircraft being stolen.” This is not really my answer, but it is the closest fit. Often I simply do not reply because of restrictive choice answers.Rae Willis

I never worry about anyone stealing my aircraft even if I leave it unlocked with the keys in it. It is a Luscombe 8F. That is the nice thing about owning a Luscombe: No one will steal it.Vernon Childers

A Pilot’s History: Chap. 7 — Air Races

I really enjoyed Carl’s story and think he is missing a bet not writing a book (Skywritings, Mar. 17). I know I would read same. This is a great Web page. Can’t wait ’til he writes more — what a great life adventure.Ken Long

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