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 This issue begins the sixth year of publication of this magazine. The regular turnover of pilots in the operational wings (plus our very modest start) means that some of you, maybe a lot of you, may not have seen some of the earlier issues. That fact, coupled with two recent articles from some well-meaning but perhaps uninformed flight surgeons, suggests that there are at least a dozen people who have not read every word I have laboriously put down on the fascinating and tres important subject of disorientation, specifically disorientation and how it interfaces with the cockpit and head-up display, or HUD, of the F-16. I want to bring all of you up to speed. So what I'm going to tell you now falls into that general category, but does apply to any airplane, however.
First, when I talk about weather (the instrument meteorological conditions, or the IMC), I mean that we are in a condition where we have been deprived of a suitable means to keep ourselves oriented as to the local horizontal and vertical. This does not necessarily have to occur inside a cloud (although this is where it usually happens).
Just as we all differ somewhat as to our reaction to various situations that we would encounter in flight, we are all alike in that we cannot continue to function correctly for any given length of time if we do not have a horizon or at least some plane of reference to keep ourselves upright. When I say plane of reference, I usually mean the ground - if you are in a low visibility situation where the horizon is not visible - and you have some a priori knowledge of what the ground is doing under you. Lead's aircraft will also work well (if he knows what he is doing). If at least one of these references is not available, some sort of disorientation is inevitable.
Q. How can we get around this human failing?
A. Provide some sort of artificial horizon.
But providing some sort of artificial horizon by itself will not correct the problem. Furthermore, providing the fourth artificial horizon in the cockpit of the F-16 (as suggested by one flight surgeon friend of mine) will not reduce the problem by one-quarter. You already have three in your cockpit: the HUD (the best one you have), the normal head-down attitude direction indicator, or ADI, and the standby ADI.
Before any of you jump to point out that the HUD is not the primary reference, let me remind you that the USAF Instrument Flight Center, the IFC, is very close to perfecting a USAF Standard HUD symbology set that will allow just that. Despite the incredible inertia created by some rather myopic individuals who attempted to discredit the HUD with the stroke of a pen, the HUD lives and will soon be given the credit it has deserved all along. Ignorantia juris neminem excusa. In its initial form in the A/B models, it works far better than the head-down ADI. The slightly larger size in the C/D is better, and the improved symbology coming out of the IFC will make it better still.
Regardless of how good it gets, however, it is still an artificial horizon. What I said above is true, regardless of what type of aircraft we are talking about.
Well, then, just what is the key ingredient to prevent disorientation? It is amazingly simple. The key ingredient we must be aware of in combating disorientation is time (tiempo, tempus, zeit, chronos), eons to nanoseconds, tick-tock. Think of that meter on your wrist whose size is supposed to separate you from the other, shall we say, more ordinary pilots. T-i-m-e. If you do not have some sort of innate sense of time, you are lost.
 How much time has it taken you to read this far? Where did you get this sense of time? Hopefully, the genetic pool provided you with a good sense to begin with, and then you had a great instructor in pilot training who led you down the proper path. The path I refer to is the one that allowed you to catalogue this inbred sense of time against various situations you might confront in flight. I mentioned above that all of us will eventually succumb to disorientation when deprived of the proper external references. But each of us has a little different reaction to different external stimuli. Some things that would turn me upside down immediately (vestibularily speaking) would not make an impression on you for quite a goodly number of seconds. On the other hand, I might do well for a while in a situation that blows you away instantly. Each of us must recognize these varied situations and know just how much time we can devote to any task other than flying the airplane in IMC. At this stage of the game, I have a pretty good idea of what misinformation I am going to have to filter out when I am presented with a given situation. I hope you have done the same. Although some of them may overlap with those of mine and other pilots, you will still have a set that is unique to you and you alone.
Don't tell anyone about this, but I spent some time in Air Training Command as an instructor in T-37s. I used to go through a little exercise with the majority of my students to demonstrate how this sense of time applied to flying any airplane on instruments when the conditions dictated. (Although I never indicated to the students just what the exercise was and most of them hated me for it, I don't know of any of them who have bought the farm in IMC.) For those of you who have forgotten or might have never been exposed, there is a series of maneuvers designed to teach pilots basic instrument techniques. They are referred to as vertical S’s and are further broken down into vertical S A, vertical S B, and so forth. When you get to a vertical S D, you are expected (in a T-37) to climb and descend through a 1000-foot altitude band, maintaining 160 knots calibrated airspeed and 1000-feet-per-minute rate of climb and/or descent. Further, you do this in a thirty-degree bank. Each time you reverse the vertical direction, you are expected to reverse the direction of bank.
It is not as difficult as it sounds. It is designed to teach the pilot a good instrument crosscheck and an ability to use the instruments to determine just what his aircraft is doing and if it is doing as he wishes. That is, is he the pilot or the passenger? As soon as it became apparent that the student pilot was in the ballpark as to flying the vertical S D, I would simply ask him what the minimum descent altitude, or MDA, was for the automatic direction finder/instrument landing system approach into Norton AFB, California.
The usual first response out of my student was an incredulous look as if I were crazy. (Watch your airspeed. Well, what is the MDA? You overshot your altitude. I'm waiting. You don't know? You're fast. Watch the bank angle. If you don't know, where can you find it? Aha, yes it is in the approach plates for southwest US. You missed your altitude again. Your rate of descent is too high. Where are the approach plates? You don't know? You're fast again. How about the map case? Your vertical velocity is too high. You're overbanking.)
You get the idea.
The whole point was to show students that it is possible to do more than one thing at a time if they can budget their time. If they got real good at this exercise, I would add little items, like starting to pull circuit breakers so that they didn't have all of their instruments, all the while insisting that they fly a perfect vertical S D. Some of you might feel like this is the Marquis de Sade approach to instruction, but I had a definite reason.
By insisting that the students do what I asked, I felt that in the future they could fly the airplane on instruments, with distractions, and with a degraded aircraft all because they had a good idea where the priorities properly lie. That is, the most important thing is to fly the airplane, knowing what time you can spend doing other tasks, even if the airplane is not completely sound. I know some of the students hated me for being such a hard-ass, but I was after making them good pilots even when they did not have all of their normal senses available to them at the time. (They might not thank me, but their mothers will.)
I have observed that many training efforts have simply identified the reasons we cannot function in IMC without enough effort to equip pilots with the skills necessary to overcome this deficiency.
I saw a fairly recently produced film that showed the pilots the danger of disorientation. In it, the pilot crashes on a night range mission and then we get to listen in as to the explanation of just what happened. Maybe you've seen it, the one where the pilot wakes up in the aircraft graveyard and has the situation explained by the old trickster and his comely assistant. The scenario has our late hero pulling off the pass in a left forty-five-degree climbing turn and not realizing that he is having problems and ends up buying the farm in a right 135-degree bank descending turn.
The trickster explains all the things that you have heard before - about how our vestibular senses can be fooled in flight - to show why our hero was fooled. He goes into such things as cockpit lighting, reflections, workload, and many other minor and/or major items that contribute to spatial disorientation.
Some of the recent articles from the flight surgeon community go even further afield. One article I remember was published in the middle of 1990 and was intended to inform F-16 pilots of the dangers inherent with flying the F-16. The author points up such facts as the missing canopy bow in the F-16. If you are flying visual meteorological conditions, or VMC, the canopy bow has nothing to do with it, as almost all pilots are quite capable of determining that their head and not their seat is the closest part of their anatomy to the canopy. That is, the head is always up in relation to the airplane and, if the head is pointed at the sky, the airplane is rightside-up. Voila. If you truly are IMC, there is nothing against which you can compare the canopy bow anyway. The author made the point that the HUD is directly in the pilot's line of sight. If somebody can point out to me a better location, I'm listening. He points out the T-38 is a better aircraft because it is "designed to vibrate in a turn or at higher airspeeds, effectively saying to the pilot that he is performing the maneuver properly." For Pedro's sake, do you really think that Northrop engineers intentionally designed buffet into the T-38? If they could have accomplished the same thing buffet-free, they would have done so in a heartbeat.
And listen to this: He says that the small size of the cockpit contributes to disorientation in the F-16. Have any of you seen an A-4 or any of the Mirage series of airplanes? Talk about your small cockpits. I don't recall seeing any of these airplanes littering the countryside after the pilots became disoriented. Good grief.
All these points, along with several others the aeromedico mentions, have much to do directly with the pilot's becoming disoriented. The fact remains that we can all fly airplanes as long as we have access to the proper external cues. Without that access, we need some artificial device.
While all of the above might be considered to be outside contributory causes, none of the facets covered in the movie nor mentioned by the medical folks address the basic reason that the pilot screwed up and the airplane crashed: The pilot was not paying enough attention to time. All of the items mentioned in the film and in the articles from the medical community are only a list of items that you should already know about if you have catalogued your responses in the airplane when you are deprived of the correct outside references. We all know what will happen in the weather or in any other period of reduced visibility, such as low-level flying at night. We all should be aware that, in a very short period of time, we can no longer continue to fly correctly without some help. If I take any of you and ask you to drive your car across a large parking lot blindfolded, you will not be able to continue in a straight line for very long. It is even worse when we try to do it in an airplane in three dimensions. But if I let you peek occasionally, the task is simple. The task is also simple in an airplane if I let you look at the velocity vector/pitch ladder relationship on the HUD or on one of the ADIs in the cockpit from time to time.
And here is the key definition to the whole problem. Once we have become comfortable with how much time we can spend away from whatever artificial horizon we enjoy the most (and you probably already know I strongly favor the HUD), it is very important that you understand what I mean when the time has elapsed and it is now time to look. As soon as it becomes necessary to fly the airplane on any sort of artificial horizon, it means that we throw away completely half of how we keep ourselves oriented. (It is really much more than half.) As soon as we have to use an artificial horizon, we no longer have the luxury of using any sort of peripheral cue that we do without any conscious effort when we are VMC.
So when I say look at the artificial horizon, I'm referring to a conscious act: a cognitive, foveal (foveacentralis, for you pre-med majors) stare at the artificial horizon. You must spend some finite period of time looking (refer immediately to the first part of the preceding sentence) at the artificial horizon of your choice. You cannot depend on your peripheral vision to keep track of the artificial horizon. You must make a continuing series of looks at the HUD and/or ADI in order to keep yourself rightside-up.
The reason that the HUD is so very much better is that in the same time you spend determining your attitude looking at an ADI, you can determine both your attitude and a large measure of the aircraft performance looking at the far-better HUD. In addition, the extended horizon line of the new IFC standard symbology also gives you a quicker mental picture of what the real horizon is doing in comparison with your airplane. I'm sure that you'll love it. So regardless of how many ADIs you festoon around the cockpit, none of them do any good because none of them will interreact correctly with your now-lost peripheral vision. You must look at the instrument to do yourself any good.
Let me give you a couple of what-ifs. Flying at night very close to the ground is a situation with which I am not unfamiliar. Using some combination of night-vision goggles, fixed or head-steered forward-looking infrared, or FLIR, I frequently find myself somewhere in the twilight zone (pardon the pun) between day, VMC and night, IMC.
Although the night-vision systems go a long way to help me see what is going on, I sometimes find conditions where the going gets very difficult if not impossible. In such a situation, I cannot depend on my daytime peripheral vision to keep myself oriented. The situation is further complicated by the fact that, at 100 to 200 feet in excess of 500 knots, I have only a couple of seconds where the wrong attitude will result in hitting the ground. Forget just being disoriented. As a result, I am forced to spend a considerable period of time looking at the HUD. The ADI will simply not tell me all the information quickly, as the HUD does. Be aware that the duration of each look may be very short, but nevertheless it is a cognitive operation as I described above.
It really gets interesting if I am required to perform something head-down in the cockpit. At that moment, it quickly gets to: think what it is I need - look - move my hand to where I think the switch/info is contained in the cockpit (in an A/B, it is usually on the fire control navigation panel; in a C/D, it is usually on the integrated control panel) - look - glance to see if my hand is where I think it is - look - move the switch - look - observe the result - look, ad nauseam. In this situation, if I have not looked at the HUD for more than about one second, the bells and whistles are going off in my head big time. In other words, I find myself in a rhythm of looking and then doing some other task, the frequency of which is determined by conditions I find myself in. It is just that easy.
In the film I mentioned, our now-dead hero goes into a left, forty-five-degree-bank climbing turn, gets engrossed with looking for lead, and supposedly allows the airplane to roll into a right 135-degree-bank descending turn and hits the ground. Now think about that for a minute. I'll wait.
Even if we assign a roll rate of twenty degrees per second (we are all capable of detecting roll rates with much lower thresholds), it will take nine seconds to roll this 180 degrees and then some measure of time until ground impact. What was our hero doing all this time? Why didn't he catch the aircraft roll attitude in some intermediate position? If we assign more realistic roll rates to the problem (those slow enough that we would be guaranteed we would not detect that we were rolling), el piloto had a huge amount of time to realize the situation and make the proper corrections. What should he have done? Look for lead: His internal clock has gone off because his preprogrammed time assigned to this situation has run out. Look at the artificial horizon of his choice. Look for lead. Again, to the artificial horizon. Ask lead for his position. Look. Decide if lead's position is within the gimbal limits of the radar. Look. Position the radar to scan for lead. Look. The pattern continues as necessary. Get the picture? In the Dash One, the first part of any emergency is maintain aircraft control. It does no good to accomplish all the commands if you hit the ground immediately thereafter. It sometimes becomes necessary to look at the artificial horizon at the expense of every other task.
Learn to recognize these situations and there will never be an excuse to become disoriented. This is all true regardless of what type of aircraft you are flying, not just for the F-16.
Remember: T-i-m-e. It will keep you out of trouble.
Check Six, if the situation at hand will allow.
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