Saturday, July 14, 2012

Viagra Use and Safe Flying


If you desire safety in flight, continuous use of Viagra is not a good choice. The use of Viagra for temporary relief from erectile dysfunction is well known. Its continuous use by pilots, without thought to flying, is subject to investigation.

One side effect is blue - green color discrimination. This inability to discern one phase of color blindness may cause danger in instrument flying weather conditions and night flying. With the advent of color displays in navigation and weather instruments presents problems for color vision deficient pilots from the use of Viagra.

Viagra can affect a pilot with unknown cardiac disease during sexual intercourse at 5,000 feet or more. If this happens in high altitude conditions on earth it would be grounds for flight disqualification medically. Mile High Club? What is the pressure altitude in an airline? What about passengers on Viagra that are visiting mountainous resorts?

I am a "nut" for a variety of license plates-okay,some plates.

You take 50 mg doses of Viagra one hour prior to sexual activity. You can increase and take 100 mg of Viagra a short time later. This drug is rapidly absorbed within a time frame of one and a half hours. An early morning flight may cause distraction from the effects above. Full attention to the instrument scan could be compromised by the four and a half hour half life of Viagra. 

Older pilots that take Viagra have trouble with their liver metabolism of Viagra. The forty percent decline of Viagra means the active ingredient stays in effect longer than for a young pilot with erectile dysfunction. The exposure of the older pilot to danger is longer. The ability of the older pilot to react to unusual situations is further compromised by the use of Viagra.

Friday, July 13, 2012

Ground Effect

Ground Effect

When an aircraft is flying at an altitude that is approximately at or below the same distance as the aircraft's wingspan, there is an ground effect. The cause is the interruption of the wingtip vortices and downwash behind the wing. When you fly a plane very close to the ground the vortices are unable to form fully. The result is lower drag which increases the speed resultant force. If the airplane attitude hasn't changed the net result is increased downward force of air that pushes the airplane upward. Thats "ground effect." Low wing aircraft experience more ground effect than high wing aircraft. Runway surface construction can affect the ground effect. Cement construction causes more ground effect than grass. Encountering turbulence in the vortices because of rough surface conditions will destroy ground effect earlier in an approach to landing.

If the drag is reduced you can reduce engine power to maintain the same speed in the same aircraft attitude. Lowering power more, at the same aircraft attitude, will allow the plane to descend. As you approach touchdown the ground effect will increase and you can bleed power down to land. At this point ground effect dissipates, the angle of attack can increase until the plane stalls just as the wheels touch the runway. Over-controlling, while in ground effect, can result in dangerous ballooning.

Angle of Attack and the fine tuning of air mass forces pushed down that is slightly greater than the force of gravity (planes weight) is the secret to ground effect dissipation. No gross movements of the controls.

Thursday, July 12, 2012

Herbal Medicines and Flying - Possible Dangers

Herbal Medicines

This is a partial list of more common herbal medicines. Just the side effects that may interfere with your ability to fly are listed. Please consult your physician with the normal use of these medications. Keep in mind that extensive, tightly controlled investigations of herbal medicine, in most cases, are not done and/or incomplete. Dosage is not correlated to sex, height or weight. 


It contains coumarin, an anticoagulant. Like other anticoagulants it should be closely monitored by a physician if you take chamomile.

May, with long term use, suppress the body's immune system. Problems that cause liver damage may occur.


Side effects include ulcers and gastrointestinal irritation. If you take it for migraines and stop taking it a rebound headache may occur. Don't use it if you take warfarin and other anticoagulants.


It should not be used with warfarin, an anticoagulant, because garlic affects clotting.


Like garlic it affects clotting. Consult your physician.

Seeds are toxic but extract from leaves is nontoxic. Don't use with non-steroidal anti-inflammatory drugs, anticoagulants, anticonvulsant drugs or tricyclic antidepressants. 


Side effects are high blood pressure and tachycardia. Don't use with warfarin, heparin, nonsteroidal anti-inflammatory drugs, estrogens or corticosteroids, or digoxin. Don't use if your diabetic. 


There are toxic components in goldenseal. Consult a physician for details specific for you.

 Melatonin is a hormone produced by your body. Hormone abuse is dangerous above normal body concentrations. Approved by the FAA but only on individual cases. Consult a physician

St. John's Wort

Side effect is sensitivity to light, but only noted in people taking large doses of the herb. 

Saw Palmetto

Side effects are gastrointestinal upset and headache, both mild.


Should not be taken with other sedatives.

Wednesday, July 11, 2012

Illusion of Climbing Faster After Take-Off

Climbing Illusion

The "False Climb" Illusion is very real and very dangerous. It is difficult to understand and kills many people that succumb to its effects. 

One, of significance, is the crash of a Kennedy family member who took off over the Atlantic Ocean at night. I believe this was a false climb disorientation. Kennedy was not instrument rated. 

Illusions are predominately misinterpretations of aircraft attitude by your brain. We learn, from infancy to our lives today, to trust our sense of sight, proprioceptors and position and balance as to our attitude with respect to the Earths surface and the force gravity.

When the visual horizon is limited or missing, like over the ocean on a dark night, the possibility of an illusion is quite high. Illusions affect pilots to different degrees. Experienced,  instrument rated pilots are just as likely to succumb to the illusion of climbing too fast as beginning pilots. You must recognize the possibility of this illusion. Why? 

When you are taking off, on dark nights, with visual reference limited, the possibility of crashing into the ground or water is very high before you can initiate a recovery.

If you read posted material on this blog the importance of the Inner ear is very important in attitude orientation in conjunction with your vision. Earth bound folks depend on vision and gravity to assess attitude. In flying, you add one additional component - acceleration in a straight line. 

If you like State Fairs and carnivals they play mischief with your senses using varied acceleration in their rides. Sickness associated with amusement park rides is not unusual.

Another name for this illusion is the Somatogravic Illusion. Basically, this treacherous event involves the signals the inner ear  produces that are incorrect though they may feel correct. These sensory illusions occur because flight is an unnatural environment. Our senses are not capable of providing reliable signals that we can interpret and relate to our position in three dimensions without visual reference.

Your brain receives continuous signals from the inner ear, gravity and proprioceptors to tell you the position of your head. Now introduce straight line acceleration. This may occur from a sudden increase in power and/or a sudden dive in a plane.

What type of message is sent to the brain when straight line acceleration takes place? The illusion is the conflict between where the head attitude position actually is and what the head attitude seems to be from the linear acceleration.

When you don't have visual reference (like the horizon) the brain doesn't receive information from the eyes that corrects the feeling that the head is tilted backwards rather than accelerated.

If you remember the post on diving an airplane with respect to what makes a plane become airborne. In a vertical dive there is still lift being produced that, when combined with the force of gravity produces a resultant force vector that moves the aircraft along its original linear path while diving. In the illusion under discussion gravity and linear acceleration produce a resultant force that the inner ear senses.

Remember, man is used to gravity and vision to determine the bodies attitude with respect to the surface of the earth. Now make the connection to the position of the head. 

Without visual information, the resultant force from a straight line acceleration in a plane moves in a rearward direction that sends a signal to the brain that, just like on the earths surface tells you your head is tilted backward.

Suppose Mr. Kennedy, waiting for clearance from the tower and able to sense his position normally, receives information about the position of his head correctly from the brain. Think erect position attitude. Once he is cleared for takeoff and applies power to the engine, the straight line acceleration acts on the inner ear along with gravity. The information the brain now sends to the pilot implies his head is tilted backward. 

When the airplane becomes airborne and enters an environment not supported by vision (like a nice completely black environment over the ocean a short distance from the end of the runway at a coastal airport) it begins to climb, and, under climb power accelerates even more. The illusion that your head is tilted backward even more is caused by the increased acceleration of the plane as it continues to climb.

Remember the proprioceptors that are located in the muscles that send signals as whether you are leaning one way or another, etc. Well, since the actual attitude of your head is still erect, the brain sends signals to you that contradict the tilting of your head and reasons the nose of the airplane must have a higher than normal attitude position! Ahh! You're experiencing The Climbing too Fast Plane illusion. You experience this as a powerful nose up illusion when your actual climb is normal.

Like any pilot who experiences this illusion does, you push forward on the yoke or stick to correct the perceived "nose up" attitude of the plane. Guess what - when you push forward on the yoke the plane accelerates in the dive and the illusion intensifies. This results in a very powerful illusion that you may lose control of the aircraft. Before you have a chance to lose control you crash into the sea. Since this in response to an illusion the aircraft hits the water surface in a near level position at a high rate of speed. the result is a fatality of one or more folks.

If you experience this illusion it is imperative that your panel scan is increased and you note your aircraft attitude is what it should be to overcome the effect of the illusion.

Tuesday, July 10, 2012

Friction - Friend or Foe (Visual Illusions)


You know when your automobile begins and stops a turn. If you turn to the right your body moves toward the left and you sense pressure caused by centrifugal force. The brain tells you that a turn is in progress. The force stops when you stop turning. Your brain tells you the turn has stopped. Your vision corroborates the information.

In flying you sense you have stopped because of friction. A little background on the structures involved before we discuss friction and its role in a coordinated turn in flight.

Sensory information of balance and position is provided by the 'vestibular system' . Tiny structures deep within our ears called 'semicircular canals' and 'otolith organs' sense changes in head position. The semicircular canals and otolith organs provide position and movement information to assist with maintenance of balance and fixation of the eyes on objects. 

This connection between the inner ear and the eyes helps us keep our eyes on an object while we move our head.

These connections also have the potential to cause illusions such as the 'vection illusion' that occurs when you are stopped at traffic lights and the car next to you edges forward. The forward movement of the car next to you, if viewed in your peripheral (ambient) vision, your brain interprets as a rearward movement of your car. So strong is the illusion that you are momentarily convinced that you will roll back into the car behind you and respond by braking. In instrument conditions where visual reference is missing the visual illusion below can happen to an inexperienced pilot. 

The semicircular canals contain a fluid called endolymph. The solid walls of the semicircular canals come into contact with the endolymph. There are hair-like structures that extend into the semicircular canals. When you are in straight and level flight the fluid, endolymph, and the semicircular canals are nor stimulated. If you begin a standard rate turn the endolymph lags behind the semicircular canals because of friction. The hairs extending down into the endolymph from the semicircular canals lag behind too. This stimulates the brain to detect a turn. The friction, on the endolymph, from the walls of the semicircular canals soon (20 seconds into the turn) brings the semicircular canals and the endolymph into synch (both moving at the same rate as the turn). Now the tiny hairs also are moving at the same rate and the brain interprets this as "no turn!" This causes the pilot to exit the turn. (Assume this is a non-instrument rated person) When he exits the turn the semicircular canals stop moving but the momentum of the endolymph continues for about 20 seconds. Here is where the illusion (graveyard spiral) begins. The endolymph now pushes the tiny hairs in the opposite direction. This sends a message to the pilot that he is turning in the opposite direction even though he is straight and level. He may, at this point, lean back in the direction of the original turn he was in to "feel" better or he re-enters the turn to his original bank. This illusion is so strong even ATC people can talk the pilot out of the increasingly steep bank.

Now you can understand the role of friction in flight. In a perfectly executed aircraft turn the effect of centrifugal force does not cause the brain to tell you that you are in a turn. In a car it does tell you a turn is in progress.

In the semicircular canals the friction between endolymph and the bony canals sets you up for the illusion.

Instrument training and your trust in what your instruments are telling you about the attitude of the plane will prevent you from entering the "death spiral."

T - 50 "Bamboo Bomber" Cessna


Hughes Aircraft (Cessna Dealer) located at Capitol City Airport in Lansing, Michigan is no more. Memories linger long after the facilities disappear. 

In the 40s and 50s Hughes Flying Service was the local hangout for all interested in flying. Heated discussions about planes, on a long leather coach facing out to a large apron that contained a variety of planes, was always underway.

Harvey Hughes and Dick Marsh (Chief Pilot) were available to keep the discussions under control. Of course, selling new and used planes was a business and prospective customers were always in attendance. 

One day a customer wanted to fly the old "Bamboo Bomber" parked out on the apron. It was still certified to fly. Harvey, a WWII aviator was more than willing. He asked my Dad and me to come along. The prospect was a friend of my Dad.

This was a transition time from tail-draggers to tricycle landing gear aircraft. The twin engine "Bamboo Bomber"was one of the last veterans of WWII used in training. The Cessna 190 and 195 evolved after WWII. 

The taxi out to the active runway was uneventful and the client was in the left seat with Harvey in the role of instructor. On take off the fun began. The client was over-controlling and the twin engined Bomber was zigzagging down the runway before the tail lifted and we managed to get airborne. I was pretty sure, as a 13 year old, that a crash was imminent and my young life snuffed out. Relieved, I turned to my Dad and remarked, "Pop, that was pretty scary!" My Dad just looked at me and said, " Son, don't forget we still have to land!" 

You can visit a web-site that is dedicated to the "Bamboo Bomber" by using the Search Function on your computer. It was a great era in flying, the 50s, when servicemen were returning to civilian life and they faced bright future. This was just a little journey into the nostalgia...

Monday, July 9, 2012

Why do we experience Night Vision Illusions?

Night Vision Illusions

Cones are primary color vision receptors located centrally on the retina of the eye. Cones don't play a major role in night vision. A peripheral location of rods, for night time vision and/or dim light , are responsible for the basic reception of images created in night flying. The impairment of the rods by bright light can create night illusion conditions. You are susceptible to these illusions as your rods recover.

Rods are 10,000 times more sensitive to light than the cones, making them the primary receptors for night vision.
The importance of time for preparation and/or recovery for rods plays  a factor in night vision. 

For example, from a safety point of view, remember the limited view of the highway after facing the bright lights of an oncoming car? Sure you do. It takes a little time for your "night vision" to recover. You can recover faster if you close one eye and focus the open eye directly at the oncoming cars headlights. Closing one eye preserves some rods for immediate use when you open your one closed eye after the car passes. No bright lights - no temporary shutdown of the rods functions. Why look directly at the bright light source - it focuses on the fovea for day light vision, not the periphery of the retina reserved for night vision. This may preserve enough rods to help your vision and prevent night-time illusions.

To see an object clearly at night, you must expose the image to the functioning rods to interpret the image. This can be done by looking 5° to 10° off center of the object to be seen. The example above involves a car. You can locate a light switch in a dark room by looking a few degrees away from the switch location. This can be tried in a dim light in a darkened room. When looking directly at the light, it dims or disappears altogether. When looking slightly off center, it becomes clearer and brighter.

When looking directly at an object, the image is focused mainly on the fovea, where detail is best seen in bright light. At night, the ability to see an object in the center of the visual field is reduced as the cones lose much of their sensitivity and the rods become more sensitive. Looking off center can help compensate for this night blind spot. Along with the loss of sharpness (acuity) and color at night, depth perception and judgment of size may be lost if the rods are incapacitated.

While the cones adapt rapidly to changes in light intensities, the rods take much longer. Walking from bright sunlight into a dark movie theater is an example of this "dark adaptation period" experience. Older people will require more time to adjust to dark rooms than younger folks. It is embarrassing to stand in the aisle before you can find a seat. Remember that when you fly. The rods can take approximately 30 minutes, or more, to adapt to darkness. A bright light, however, can completely destroy night adaptation, leaving night vision severely compromised while the adaptation process is correcting over time. 

Red flight deck lighting also helps preserve night vision, but red light severely distorts some colors and completely washes out the color red. This makes reading an aeronautical chart difficult. A dim white light or a carefully directed flashlight can enhance night reading ability. a fishing head light is one way to focus on a map and still have both hands free to maintain control of your plane. 

While flying at night, keep the instrument panel and interior lights turned up no higher than necessary. This helps to see outside references more easily. If the eyes become blurry, blinking more frequently often helps.

Diet and general physical health have an impact on how well a pilot can see in the dark. Deficiencies in vitamins A and C have been shown to reduce night acuity. Other factors, such as CO poisoning, smoking, alcohol, certain drugs, and a lack of oxygen also can greatly decrease night vision.

Sunday, July 8, 2012

Night Visual Illusions

Autokinesis and False Horizons


Staring at a single point of light against a dark background for more than a few seconds illustrates the illusion. After a few moments, the light appears to move on its own. To prevent this illusion, focus the eyes on objects at varying distances and avoid fixating on one target. Be sure to maintain a normal scan pattern. The illusion imitates the movement of light that may cause disorientation.

The Cessna Skylane has a nearly complete wrap-around windshield. If you follow a traveled road, with little lighting in the surrounding area at night, you will experience autokinesis. When you check the rear windows, of a Cessna,  a string of dim lights that appear,in your vision, curves around towards the tail. It creates a sensation of turning to the left if the road, with car lights, is on your right. Vice-versa if the road is on your left. 

Autokinesis, with just one spot of light moving, may induce a similar illusion. 

The illusion is so powerful you need to concentrate on your instruments to recover adequately.

False Horizon

A false horizon can occur when the natural horizon is obscured or not readily apparent. Bright stars and city lights generate the false horizon. It can also occur while flying toward the shore of an ocean or a large lake. Because of the relative darkness of the water, the lights along the shoreline can be mistaken for stars in the sky.

You may think your in a relatively steep climb and you counter this by pushing forward on the yoke. It may cause a crash before you discover the illusion.

Knowing what to expect, if conditions deteriorate en-route, can save your life.