Flight Surgeon's Corner

Back just after the first Gulf War, before God created KBR dining facilities, we had some pretty terrible MREs. The F-4 G weasels were also relegated, as was everyone else, to drone for hours patrolling Iraq. Morale was dependant on whatever we could do to entertain ourselves.
There was a former Iraqi Army outfit over which our patrols routinely fell, that would repeatedly spell out very large "graphically insulting" comments directed at us that we could read from the air in a large field near their barracks, in addition to the occaisional, but unactionable, groundfire potshots.
Aviators are many things, and creative genius is one of them. One day before his 4-ship patrol flight lead, Spike, a true American Hero, canvassed all of Shaikh Isa Air Base and happily collected a few hundred packages of that most infamous of MRE entrees, the prepared pork patty in sauce. These packages of bounty were brought to the planes the night before, and placed in the recesses inside the speed brakes below the wings, and the speed brakes closed over them.
Well, indeed, a fresh and visually disturbing insult was laid out in the field by the Iraqi barracks that day. Spike rocked all 4 planes into fingertip for an ...er... low pass directly over the Iraqi camp in tribute to their fine efforts. On a predetermined signal, all 4 planes popped the speed brakes and it rained pork patties, hundreds, on their camp, which we were sure they would take as a magnanimous gesture of our good will and appreciation.
This sortie became to be known as the famous "Pork Patty Laydown"
Life was good then.

 

This is all very true, and why one should seriously look at LSA flying as they get older, or less well.

You should never lie - everyone stands to come off badly.

And, along with disqualifying medical conditions, lying can prompt the FAA to "DENY" your medical certification. If you are currently in denied status, then you cannot fly under LSA rules, which only require a driver's license. If you have never been denied, previously denied but re-instated, or if your most recent medical is just expired then you may qualify to fly under LSA rules

 

In high performance and aerobatic flying, it is common to accellerate the body on the lift vector, commonly referred to as the G-z axis. The body may be subjected to other accellerations, but this is the most common. Since we are typically sitting, the multiplied force of gravity tends to pull everything down towards the feet. Let's look at two things that happen physiologically when a human is put in this environment for which it was not designed for.

1. Reduction of of cerebral/ocular perfusion. The heart has to pump (push) blood up to the head by means of generating pressure, which can be thought of as a standing column of water. The blood flows as ts long as the heart and circulatory system can generate enough pressure over the weight of the column of water at the top -- and at the top is the brain and eyes. So, as G is added, the amount of pressure needed to maintain blood to and through the eye and brain capillary beds goes up as the force of gravity acting on that column of water goes up. If it goes up higher than the heart can generate pressure to overcome it, blood flow to the eyes, then the brain slows down, and then stops, followed momentarily afterwards by stoppage of function until the blood pressure comes up or the G goes down. Simple physics.

Now, the body has ways of sensing reducing blood flow to the brain, and has compensatory mechanisms. But, if the G ONSET RATE is to fast, the body will not have time to compensate.
So, if you are pulling g's, you can do better with a slower g onset to allow the body to kick in and for you to start any anti g straining maneuvers, if needed (more on these another day).

With a slow G onset, the average RESTING G-tolerance of most everybody is 4 - 5 Gs, give or take, and is affected by a number of things. Tall people have a laonger distance to push blood up to the brain, so they typically do not do as well as sawed off little ****s. If your resting blood pressure is low, it may not can respond enough to overcome the higher pressure requirements of high G accellerations. That is dehydration, even in small amounts if due to heat, illness or low input is terrible terrible terrible for G tolerance (and many flying peformance issues, notably increased fatigue). And, pure aerobic training, which tends to lower heart rate and blood pressure, is not the best for fighter pilots rather a more balanced anerobic aerobic training is best.

STAY HYDRATED - this is so simple and affects so many flying related performance issues. And remember, if you are ill, or recovering from an illness, you are likely to be carrying some dehydration and should really best not be in command of an aircraft. AND, if it is hot, your fluid loss rate will be higher and you will become dehydrated and fatigued faster. You've heard all of this before, I know, but it bears repeating.

2. Spatial orientation. The human middle ear, which detects orientation and accellerations, is designed exclusively for the one G environment, and is totally unreliable once one G is exceeded - therefore - ALL accurate spatial orientation in greater than one G environments is VISUAL - if an outside horizon or artificial indication in the cockpit. You will not know up from down under G unless you have an external visual reference. I cannot emphasize enough how important this is - the concept that flying is a VISUALLY dominate environment for spatial orientation. We lose people - good people - every year due to disorientation from lack of accurate visual references.

Lots more to talk about, but it's bedtime for Bonzo.
Hope this helps as we go along.