AVmail: Jan. 22, 2007

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TFRs at Border Patrol

Gee, if you close large blocks of airspace for UAVs to patrol the borders, and advertise the fact in advance so GA won't be in conflict (AVwebFlash, Jan. 15), it doesn't take a genius to see that all the bad guys have to do is read the NOTAMS and avoid detection accordingly.

David Pray


As a Canadian, I am dismayed with the supporters of Homeland Security who continue to finger-point north of the border. Whether it's a "breeding ground for terrorists" or claimed to be the cause of the power outage on the East Coast a few years ago, it seems to me they are playing on Americans' fear and using it to build their own little empires. UAVs creating TFRs and Blackhawks on patrol seem like overkill to me. Motion sensors/cameras and a smaller reactionary force to them, to me, is all that would be needed.

Dallas Hanson


Pelican's Perch: Three-Engine 747

Cast my vote solidly with Barry Schiff. I have 13 years as a B-747 Captain and I would never have continued the flight (Pelican's Perch, Jan. 7). There are a multitude of reasons why continuing was a very poor decision. Safety should always be the number one concern.

Should a second engine have failed for any reason (perhaps from unseen shrapnel off the failed engine?) would there have been sufficient aircraft performance remaining to clear the high terrain encountered right after a fairly heavy-weight departure? Most other reasons for not continuing have already been discussed by others (lack of suitable airports over desolate areas, the ocean crossing, etc.). I agree with all of them except the thought about continuing on to ORD (or somewhere down the line over relatively populated areas where major airports are always nearby) unless the performance data indicates that the loss of a second engine will still allow the aircraft to comfortably clear the mountains. Even then, keep in mind that at the lower altitudes both turbulence and mountain waves would further diminish any published performance.

A last thought: When minor things start to go wrong, they can very often snowball and make things get very wrong.

Far better to dump some fuel, return to the blocks, and get the ship 100% airworthy again. Expensive? Yes. But it absolutely would've been the safest thing to do. To do anything else was a major compromise of safety.

Harold Bemis

John Deakin Replies:

Thanks for writing. We'll have to agree to disagree, but I respect your opinion.

Of course safety should always be the number one concern. But we don't deal in absolute safety, for that would mean never boarding a passenger, or starting an engine.

If they'd lost a second engine, there absolutely would have been sufficient aircraft performance remaining to clear the high terrain. I think they started out at FL270, and were probably at that altitude long before they reached serious terrain. With the second loss, they would have started dumping fuel, and drifted down very slowly, headed for any number of nice airports. During the climb and first couple of hours, they had plenty of time to spot any anomalies in another engine. They had to fly for 45 minutes or so just to dump fuel, if they wanted to land.

Plenty of fine airports along the way until northeast Canada, and by then they were light enough to remain above FL200 even on two. By the time they got there, if there were no abnormalities with the remaining engines, the odds of another failure would have been the same as the odds against the first failure. They do happen, but they're very, very rare.

Do you accept the idea of a 777 making that flight on two? They why not a 3-engine 747? Both are safe enough.

If they'd dumped fuel and returned, the total cost would have been in the millions, with 360+ passengers greatly inconvenienced. I don't agree that returning to LAX was a good option, or the safest option.

But like I said, let us agree to disagree. You're not alone, but neither am I. The investigation fully approved of what they did, found there was nothing illegal or unsafe about it.

John Deakin
Columnist


MacLeod/Bell 52.5-Spin Video

You should -- perhaps in the interest of safety -- have a comment with the video that to go more than a turn and a half and recover puts you in the non-demonstrated test pilot category (Video of the Week, Jan. 15). Per normal and utility category requirements per FAA certification (I'm not exactly sure what they are but perhaps you guys could research this), some aircraft may not be recoverable after numerous turns? I absolutely think it is critical training that most people are void of and would save many lives if pilots had a more complete understanding of their specific aircraft characteristics. Examples: The Grumman Tiger and also the popular T-tail Tomahawk have potential problems with spins. The theory being to train to stay out of spins but not what to do to get out of one. By the way, what about an inverted spin?

Your web site is superb; keep up the education. The march toward safer flying never ends.

Thanks for all your work.

P.D. Schmidt

AVweb Replies:

Due to circumstances in my busy schedule, the video went to press before I had a chance to write some commentary, which would have included a short tribute to Bill Kershner.

This aircraft (Cessna 152 Aerobat) is certificated in the acrobatic category, meaning that it is recoverable at any phase of an upright spin with the proper recovery technique. It is approved only for upright spins, and while there are approved methods for accelerating and flattening spins in this aircraft (and recovering from them), neither of these attributes pertains to the spin in this video. That said, there was an innate pitch oscillation owing to competition between inertial and aerodynamic forces with the CG near the aft end (but still inside) the envelope.

Were we test pilots by going beyond 1.5 turns? Hardly. Please check the regs on the acrobatic category. At the time of this spin (10+ years ago), Max and I between us had taken hundreds of spins into the developed phase in the A152 (the threshold is about three turns in this aircraft). I had been in regular consultation with Bill Kershner while exploring these extended spins, and I took careful notes on all my spin flights and shared them. I sent him this video also.

That said, were we test pilots doing 52 turns? Probably, but not without wise counsel from Bill (himself a former Cessna test pilot) who knew the territory as well as anyone could, and not without careful preparation, including several other spins of over 20 turns. We had determined to our satisfaction that the aircraft's behavior was completely predictable in an extended spin. It was really just a matter of getting up high enough to recover by 3000 feet AGL, and we calculated it exactly right.

Assuming one is inside the weight and CG limits for the acrobatic category, recoverability is not an issue for the aircraft. I would never spin an aircraft in the normal category, where recoverability is a serious issue.

Train pilots to stay out of spins? Absolutely. Not train them on what to do to get out of one? You didn't mean to say that, did you? I firmly believe people should learn, precisely and empirically, what to do to get out of one, in an approved aircraft, inside the mandated weight/CG envelope. I have trained a lot of military pilots in spins in the Aerobat, and we had group debriefings in which we talked in theoretical terms about how to get out of a spin in the King Airs they were flying -- essentially recover within the first half turn or else. (Bill K. was an advisor to me on this, too.) I agree completely that we should all know the flight characteristics of the aircraft we fly, read the manual, get checked out by an instructor who really knows the model, and stay current. My students would say I'm anal about safety.

As for why those particular aircraft you mention have problems with spins ... that's a whole 'nother story. I would not spin either one of them, though I know there are pilots out there who have spun Tomahawks repeatedly with no problem.

I am no authority on inverted spins. I have done a couple dozen of them dual in high-performance, acrobatic-category aircraft, including a few crossovers from upright to inverted, but none solo. They cannot be done in the Aerobat; we'd lose all the oil.

Thanks for sharing your thoughts and concerns.

Barb MacLeod


Plastic Pilot Certificates

If the pilot certificates are going to have a photo some day (Question of the Week, Jan. 11) ... passports and pilot certificates both come from the federal government; wouldn't it be nice to consolidate it into one document?

Eric Ulmer


The Comair Crash

The reason for the Comair crash was simple and it was not the fault of controllers, understaffed towers or airport maintenance personnel (AVwebFlash, Jan. 18). The pilots simply failed to do a simple procedure that is taught to all student pilots and that is to check your compass heading while on the parallel taxiway and again when lined up for takeoff. There are thousands of operations every day from un-towered airports, many into low IFR. If we really needed controllers to help us taxi to, confirm and takeoff on the correct runway ... well, the truth is we don't, and neither did the Comair crew. They were not paying attention and a lot of people died as a result.

Ben Bailey


As a former air-carrier pilot and captain, and a school-trained (Naval Post-Graduate School) Naval Air safety officer/accident investigator, I find the COMAIR flight crew's actions completely unconscionable. Yet is seems that most people, including the FAA and "pundits," are trying to spread the blame.

No pilot should ever take off from an unlighted runway. What happened to asking the tower to confirm the "lights" on the departure runway? What happened to the crew's compass/HSI checks? Crew coordination? As soon as the runway remaining boards showed less than Runway 22 length, that should have been a "wake up call."

In mishap investigation, we call this a primary cause of "Pilot Error" with contributing circumstances.

Ryan Wilkins


Flight Services Suit Against FAA Proceeds

The article states that "About 800 employees were affected by the outsourcing" (AVwebFlash, Jan. 15). The actual number is closer to 2200. The 800 number refers to those who are eligible to be part of the age discrimination class action suit and elected to do so.

Richard Rydberg


Ohio Registration Declaration

Never mind the discrimination, what about common sense (AVwebFlash, Jan. 18)? You would actually tell that you were a terrorist? Please stop the nonsense.

Don Gay


Missile Defense for Airlines

I saw the article [about airliner missile defense systems] initially in the CNN.com site (AVwebFlash, Jan. 18). I was amazed, because the cost-trade indicated that the cost per aircraft was $1 million and the recurring was $365 per flight.

In the industry we typically figure on 20 - 30,000 flight cycles, so the life-cycle cost comes to more than $8 million per airplane. If we assume 200 passengers, they will be paying nearly $2 on each ticket (flight leg) for the defense system.

I had to cost over the life cycle of an airplane a fuel-inerting system and was hard-pressed to justify a system with costs of $1 per flight hour (which compares to about $0.05 per passenger per flight) and that is a system that is almost mandatory.

No one will buy this! At least the fuel tank explosion rate is a real number divided by the 6000-some aircraft in service. The missile defense system is 0 divided by 6000.

Some business-jet companies have entertained and even certified missile jammers for their products as customer requested installations. (How much is your CEO/VIP worth?)

It will be interesting to see how the price can be reduced to make the trade study come out in favor.

Dave Lamb


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