CATESBY: . . . His horse is slain, and all on foot he fights,

Seeking for Richmond in the throat of death.

Rescue, fair lord, or else the day is lost!

KING: A horse, a horse! My kingdom for a horse!

That famous Shakespearean plea is universal in its expression of angst over an out-of-reach goal. It is a feeling familiar to anyone who is about to begin another long haul, international trip and starting what will surely be a long, arduous day wishing — indeed, almost praying — to have slept a few hours more. It's a feeling of despair every bit equal to King Richard III's.

The science of sleep has long been far ahead of the federal aviation regulations regarding its application to crew rest. In recent years, after several tragic accidents in which pilot fatigue was a factor, the FAA set about codifying that body of science as it applies to scheduling aircraft and aircrew movement. Most of the statistics I quote here are from that work.

Accident rates for pilots who have been on duty for 10-12 hr. are 1.7 times greater than that of the general control group. Meanwhile, the accident rates for pilots who have been on duty for 13 or more hours are 5.5 times higher than the general group.

Science has shown that an eight-hour rest period during the window of circadian low (WOCL) is the best way to ensure safe and accurate performance for any individual. Putting that sentence into a document that applies to all commercial flight operations must have been a huge undertaking.

And after wading through the FAA's entire “Flight Crew Member Duty and Rest Requirements” (77 FR 330) I came away impressed that it was ever completed. In reading the document's various inputs and considerations, I would have given the authors about the same chance of success as giving a sink full of grown cats a bath.

Nevertheless, the science was acknowledged, the disagreements all heard, and the document was published in the Federal Register on Jan. 4, 2012. Most importantly, decisions were made. The 314-page document displays typical bureaucratic style and length, but the real meat comes down to the final three charts that appear on one of the last pages.

The charts somehow take into consideration the time zone to which the crewmember is acclimated, when the day begins, how many pilots are in the crew, what crew rest facilities are available and the number of hours to be flown and the length of the flight duty period (FDP). The designers accomplished a very worthwhile goal and I can only imagine the frustrations, bickering, cajoling, documenting, pleading and huge effort that went into it by all the parties concerned. In fact, most of the document deals with how those various concerns were raised and handled. Those final three charts represent amazing achievement.

One of the hardest assignments ever given me was to come up with a simple chart that allowed our department dispatchers to schedule crews in international operations without having to review each leg of a trip with me. I eventually succeeded, but reserved the right to examine our toughest international trips in the scheduling phase. Often I cut planned crew rests short and many times I extended them because I knew from experience there were situations where “normal” wasn't enough and others when “crew rest” periods were time spent awake, waiting to go to the airport. The new FAA document creates all-encompassing charts that I was not smart enough to produce.

Even though the new rules were developed for airlines and supplemental carriers, it would be foolish for those of us operating large cabin business jets over extremely long range profiles to ignore them. This new “gold standard” on crew rest has to be considered in any scheduling we do and as it turns out, most of us were probably pretty close to it anyway.

The factors affecting fatigue include:

Time of day — Fatigue is, in part, a function of circadian rhythms. All other factors being equal, fatigue is most likely, and most severe, between the hours of 2:00 a.m. and 6:00 a.m.

Amount of recent sleep — If a person has had significantly less than 8 hr. of sleep in the past 24 hr., he or she is more likely to be fatigued.

Time awake — Those who have been continually awake for a long period of time since their last major sleep period are more likely to be fatigued.

Cumulative sleep debt — For the average person, cumulative sleep debt is the difference between the amount of sleep received over the past several days, and the amount that would have realized with 8 hr. of sleep a night.

Time on task — The longer a person has continuously been doing a job without a break, the more likely fatigue will result.

Individual variation — Individuals respond to fatigue factors differently and may become fatigued at different times, and to different degrees of severity.

All crew rest and duty time limitations have one ultimate goal, ensuring pilots are physiologically ready to accomplish the complex technical and analytical skills required to achieve their flight mission. There have been times, I'm sure, when any of us would have surrendered our thrones for a good night's rest.

Gulfstream 650s, Global Expresses, and Dassault Falcon 7Xs comprise magnificent evidence that the corporate world intends to routinely fly some very long stage lengths over multiple routes on multi-day missions. With airplanes that can fly from 12-16 hr. non-stop, pilots must not only have to try to launch rested, but stay rested while the plane is en route.

The hardest of all the factors to plan for is individual variations. I have flown trips where I crossed nine time zones and slept like a baby, then travelled three more and again slept the full night. I would add that most of these trips were in a Westward direction. I have flown other trips where I do not believe I had more than horizontal-but-sleepless rest for days on end.

What I regard as a major flaw in FAA's new rules is that they require crewmembers to report when they do not feel rested at the start of an FDP. That won't happen. But if it does happen, we will see a major disruption of scheduled and supplemental overseas flying.

The simple truth is that no one ever feels ready all of the time. I remember, during Operation Desert Shield/Storm looking for a young loadmaster who had failed to report at crew show. We eventually found him sound asleep in the base chapel where he had been praying to do just that — to get some merciful sleep.

And consider the crewmember whose schedule complies with all the world's science and knowledge regarding rest periods. Nevertheless, if the night passes fitfully and sleepless, that pilot will feel as though pulled through a keyhole at show time. And should the pilot report of fatigue and the trip is rescheduled for 12 hr. later as a result, it's unlikely that sleep will follow with the whole crew now standing by. If the pilot did nod off, what would be the condition of the rest of the crew that was left waiting for the weary member to get rested? Airlines may have additional crew members they could plug into the manifest, business flight departments do not.

With this in mind, let's consider the new rules when compared to some scenarios I've experienced.

Our crew departed via commercial airlines from New York's JFK International to Athens. We were to crew a trip from Athens to Singapore, then Hong Kong, Tokyo, Fairbanks and “over the top” to London. We stopped for 36 hr. of crew rest in Athens before assuming control of the flight as it arrived from New York. Our eastbound routing allowed us to reach Singapore about an hour sooner and with one less tech stop than going through Anchorage.

We based our two-pilot duty day rule of 14 hr., night or day, on the fact that the FAA then allowed supplementals to schedule 16 hr. of duty for normal crew and 30 hr. for an augmented crew.

The new FAA charts define all scheduling possibilities in terms of an “acclimated crew,” which is one that has been in theater for 72 hr. or 36 hr. free from duty. We were acclimated to Athens.

Our two-pilot crew would, under FAR 121, now be allowed only 9 hr. of flight and 13 hr. of duty, based on a 0700 Athens report time. We flew 10 and half hours and had a 13.5-hr. duty day. The new rule requires three pilots for 13 hr. of flying and four pilots for 17 flight hours. As we would still be flying under FAR 91, we probably wouldn't change that part of the trip.

It takes 36 free hours to become acclimated to a time zone. However, if a crew is not acclimated, the pilots must have at least 10 hr. of rest allowing for 8 hr. of sleep during the period 0100-0700 in the time zone for which they are acclimated.

This often works for airlines because when a crew arrives, they can be off duty until the same flight arrives a day or two later. We landed in Singapore at midnight and arrived at the hotel at about 2 hr. later. We reported back for duty at 2 p.m. the next afternoon. As the day before had not been “extended” or during a circadian low period in our acclimated time zone, we did, in fact get the 10 hr. off with rest during the 0100-0700 time (Athens). When we reported for duty the next day at 2 p.m. and flew on to Hong Kong, we were good according to the new rules.

We were in Hong Kong for two nights and well over 36 hr. An evening trip to Tokyo with 24 hr. off was followed by a 17.5-hr. duty day, starting at 2300 (acclimated Hong Kong/Tokyo time) through Fairbanks to London. We picked up a third pilot and second flight attendant in Fairbanks and kept ourselves within an 18-hr. day, our limitation. Being Part 91 and picking up an “acclimated” pilot in Fairbanks who reported for duty at 1500 local, this operation, I feel, could be justified for us, but not for a Part 121 carrier.

Next came 12 hr. of crew rest and a return home, as passengers, in the back of our company plane. This short turn time wouldn't be allowed for most scheduled operations and I think that's valid because those folks may well be expected to repeat the same operation a week later. We weren't.

I rested well until the night before the Tokyo to London trip. Then I slept about 4 hr. and woke at five that morning. I was exhausted by the time I got to London. I did get about 3 hr. sleep in the back of the airplane on the second leg. The other pilot did the same (different 3 hr.) as we left the fresh pilot up front for the whole Fairbanks to London leg.