AVmail: November 25, 2013
Letter of the Week:
A Technological Solution to a Human Problem?
I have several thoughts about the sudden concern by the FAA over sleep apnea in pilots and controllers.
The NTSB Safety Recommendation was issued August 7, 2009. Why has it taken more than four years for the FAA to jerk its knee in response?
Has it occurred to anyone at the FAA or elsewhere that there may be a significant relationship between the reliance on autopilots and falling asleep in the cockpit? Although it's not impossible, it's hard as heck to fall asleep while hand flying. We already know from the empirical evidence of the last few years that there is obviously a significant loss of hand-flying skill due to excessive reliance on autopilots. Perhaps all of this is closely related.
With all of the marvelous technology abounding in aviation these days, how about just installing a sophisticated tilt switch in headsets which causes an alarm to sound if the pilot's head remains in a tilted position more than a few seconds? Most people who fall asleep while sitting literally nod off. They don't keep their heads upright. That would directly address the problem of a pilot actually falling asleep rather than this indirect approach of having the pilot jump through a whole bunch of expensive medical hoops, which may or may not result in keeping him awake while flying.
Take it a step further, and, as soon as the autopilot is engaged, so is the headset tilt switch. Have the system set for 10-12 seconds, plenty long enough to do anything that requires a tilted head in almost any cockpit, which would minimize false alarms.
It's not possible to eliminate human physiology problems that impact the safety of flight, but I have serious doubts that this recent concern, if followed through with new rules requiring expensive medical testing, even addresses those problems to the extent that it will benefit anyone.
The BMI was "discovered" in the early to mid-1800s and means nothing. Muscle mass is not taken into the formula, and most military pilots and athletes show a higher BMI. Maybe the FAA should go back to school and stop using junk science to further their agenda against obese people.
OMG. Talk about a disease du jour. "Sleep apnea can ... ." "Sleep apnea may... ."
Data? I presume the data is as good as the data on ECI cylinders.
Your article is headlined "FAA Medical Chief Targets Fat Pilots And Controllers" and states, "... Tilton doesn't say in his brief note what data (how many OSA-related accidents have been recorded, for instance) his staff have used to draft the new rule." Both the headline and the disclaimer are disingenuous, if only due to ignorance. A quick Google search for "OSA accident risk" will return many useful hits, including an excellent, well-researched publication by the aeromedical division:
This is a very important pubic-safety issue regarding all vehicles and all types of traffic, related to our epidemic of obesity.
You owe your readers a brief article on the actual risks to others of anyone's obesity and sleep apnea.
Dr. Daniel Johnson
You just did that for us, Dr. Johnson. Thanks.
I think what the FAA really wants to say is that they are targeting overweight and unfit pilots. Let's be honest. I've seen commercial air transport flight crew colleagues who are really overweight. I've even wondered if they could move the control column through its full range of travel.
How Not to Land?
The article on landing tips has absolutely terrible suggestions. As many instructors tend to do, they teach their students some rote procedure (like the runway through the strut) that will only work under specifics conditions, like in that airplane model with calm winds and no other traffic. Then, when pilots are flying on their own in the real world, they find the winds may be different, or they may have to approach the runway from a base entry or a straight-in final when instructed by the tower. They will realize the rote procedure they were taught has now left them without the ability to adjust.
Here's another one: "Abeam the numbers, pull off the power. If the power reduction was correct, all you'll need to do is apply the rest of the flaps." This one can be related to slowing a car from highway speed to city speed. Imagine if you had to make one change on the accelerator that resulted in a perfect speed reduction from highway speed to city speed without touching the accelerator again. That is basically what the article's suggestion is: Pull the power on downwind as though this power change should be what will be needed on final.
Flying the airplane shouldn't be a guessing game with the power. The pilot should be taught to make power reductions initially to establish a smooth and easily manageable transition to approach speed and configuration and then how to make smooth and small adjustments for the rest of the approach in order to maintain a stabilized approach no matter what the variables are.
The next time you transition from the highway to the city traffic, just think about the smooth changes you make with the braking and the accelerator to get stabilized in the city flow. The airplane is surprisingly similar, and in both cases it is pretty obvious what needs to be monitored. The article is completely ignoring the fact that pilots, like vehicle drivers, need to monitor the right things and respond on the controls as often as necessary to maintain the desired results as things progress.
Warren Webb Jr.
Flying on Three Engines
Regarding Gregory Myers's comments on the decision by the Emirates A380 to continue across the Atlantic on three engines: No one will deny that the A380 will safely fly on three engines. The failure of one engine is not concerning. Why the engine failed is critical information in the decision to proceed or divert to the closest air field.
I'm not sure if anyone in the decision loop at the moment of failure knew the exact cause. The cause may start showing up in other systems. There are many scenarios in which one engine failure could lead to another.
The pilots must have had overwhelming evidence of the exact problem to continue the flight. Not knowing the exact cause of the engine failure and continuing the flight would be poor decision-making. Fortunately the engine failure must have been a local problem and did not influence other systems.
With the understanding that two fuel pumps failed, I would then ask why they failed. If it was contaminated fuel, that could lead to other pumps failing. Speculating from the cockpit in flight is not what I want my pilots doing.
I find it amazing the thousands of hours spent by the NTSB to find the cause of an airplane crash; however, pilots can make decisions with limited information in just a few minutes whether to continue a flight. I don't have all of the dynamic information the pilots had at the moment. However, we now know what failed, and I still would have diverted to the closest air field.
In an engine failure, I think the remaining engines are there to assure a safe on-airport landing. I lost an engine in my Aztec at night in IMC 20 years ago. After getting to VFR conditions, I was ten miles from an appropriate airport but was tempted to fly to my destination airport, which was 40 miles away. I decided to land at the closest airport and rent a car to get home.
My feeling was that I did not know for certain why the engine failed. It could it have been fuel-related, so landing and renting a car to go home seemed like the right decision.
As it turned out, it was not fuel-related.
I heartily concur with the use of four engines in oceanic flight. Years ago, I was invited up front in a BA 747 when over Greenland. (Ah, those days of access to the cockpit.) When I mentioned to the captain that a friend regularly refueled in Greenland when flying his Twin Comanche across the Pond, he looked up at me and said, "A twin? If I could have five engines on this, I would."
The crew complied with regulations because they had not lost 50 percent of their engines. Was it a smart move to pass up airports once they had successfully made the crossing and press on to the Middle East? I don't think so. Not many airports can deal with the A380, but some in Europe can.
It was legal but not prudent. I always said I would never fly over the ocean on less than three engines. I finished up flying the B-767ER across the Atlantic out of JFK, so never say never.
Regarding Rohinton Darukhanawala's letter concerning squawk codes in an emergency: Transponder considerations in an emergency descent and an engine failure are two separate issues.
Transponders are changed to TA only in the event of an engine failure to prevent a TCAS RA (Resolution Advisory) "Climb, Climb" indication to an aircraft with reduced performance capability and will instead trigger the TCAS RA "Climb, Climb" indication in the other aircraft.
Switching to TA only on the transponder of an aircraft during an emergency descent would inhibit that aircraft receiving a TCAS RA indication for no valid reason.
There's no need to change any manufacturer's checklist.
Individual operators may have edited their own checklist with the approval of the regulator of their country.
The recent incident on Jet Blue with a slide inflating in the aircraft is not a new problem. It has happened many times before and is why, at Northwest, all pilots were advised to carry pocket knives prior to 9/11.
It's time to put aside ridiculous restrictions on crew members carrying the proper tools needed to do their jobs.
Capt. Dave Funk
Northwest Airlines (retired)