Unintentional erection during high G loads?

January 31, 2007 10:27 AM

Do (male) pilots ever experience unintended erections while experiencing high G loads on their body?

Pilots who regularly undergo high G forces wear g-suits to prevent the brain from being starved for blood, leading to unconsciousness. I would imagine that due to the additional blood forced lower in the body that unintended (and possibly very uncomfortable) erections are possible, but I can't seem to find any information as to whether or not it occurs and/or is a problem.

Wikipedia, Google, and the other usual sources are failing me as I'm trying to find information about this. (They are finding spammy pages and fanfic / slash, but that's not what I'm wanting.)

Can anyone help?

posted by c0nsumer to health & fitness (16 comments total)

I'm a private pilot so my contribution is not "high G", but it might be helpful anyway. I fly the very common Cessna 172.

While practicing 60-degree steep turns you develop a constant load of approximately 2 Gs. Spin and dive recovery produce at least 3 Gs, maybe more. To my knowledge, none of the aircraft at my club are equipped with accelerometers so I can't be more accurate.

However, I have grayed-out before doing the above, the colour drained from my vision, and that is supposed to occur between 6-8 Gs if I remember my phisiology of flight correctly.

All of that without any "consequences".

I imagine the Gs are introduced far more gradually in my plane than in a fighter, which might have some effect, that is to say there's less time to adapt physiologically in an aircraft of higher performance.
posted by KevCed at 11:22 AM on January 31, 2007

I have no experiential or anecdotal basis for my statements, but here's my scientific analysis:

Erections are caused by a dilation of the blood vessels via the release on Nitrous Oxide in the penis. Although blood may pool into the lower core and extremities during high-G activity, nothing has actually dilated those vessels. Therefore, even with increased pressure one may not experience an erection since the vessels remain undilated.
posted by dendrite at 11:34 AM on January 31, 2007

(Aren't most erections "unintentional" when you come down to it?)

As per dendrite's explanation, that's just not how erections work.

It's not about blood pressure of the body in general, it's about blood flow in that particular area. Do balloons spontaneously inflate when the air pressure is higher?
posted by AmbroseChapel at 12:00 PM on January 31, 2007

This won't be much help... but doesn't every guy get unintended erections? I get the big guy saying hello just from riding over the railroad tracks.
posted by SupaDave at 12:03 PM on January 31, 2007 [1 favorite]

That is not how that part of the anatomy works. If it did there would be random erections when people run into everyday high-g situations like riding a roller coaster, slipping and falling, etc.
posted by damn dirty ape at 12:18 PM on January 31, 2007

That is not how that part of the anatomy works.

Except, it does appear to be how that part of the anatomy works. I suspect pilots, in general, don’t have the exposure to the relvant pressures over a sufficient period of time for it to result in an erection. I am not remotely a doctor, nor a medical student.
posted by Aidan Kehoe at 12:37 PM on January 31, 2007

I'm not sure if this is related, but I seem to get the type of effect you describe every time I'm traveling on a commercial airplane, when the plane begins its descent. Needless to say, I am not one of those people who jumps out of his seat as soon as the plane lands. Although, maybe this has more to do with depressurization of the airplane cabin than with the Gs.
posted by metawabbit at 1:42 PM on January 31, 2007

As anecdotal evidence, I don't think this has ever happened to me. Have grayed out before, though... it's a really weird sensation.
posted by backseatpilot at 1:45 PM on January 31, 2007

I had 1.5 hours of time in a T-38 jet and we did a lot of sustained 4 g maneuvers and a few up to 7 g. My own minimal experience nets the answer "no". If you can find an F-111 pilot you'll have an authoritative answer... they are used working under to long, hard... ahem, lengthy sustained G loads.
posted by zek at 1:50 PM on January 31, 2007

Military or acrobatic pilots flying in situations where G-suits are used, are also doing coordinated lower body muscle clenches, "grunt" breathing, and abdominal tensing as techniques to raise their blood pressure and restrict blood pooling in the lower body. That's been a training maneuver since the Korean war, when it was learned that Russian "honcho" pilots were successfully flying the high performance MiG-15 fighter without G-suits, by such physical regimens.

To be effective, considerable effort must be put into such exercises. Resisting high G forces is about as strenuous as human physical exertion can get, and most pilots doing it break out in a sweat from the effort. Some squeeze hard enough and long enough to create or exacerbate hemmorroids, and others have experienced stress bleeds in capillaries in the eyes, or have developed or exacerabated other circulatory problems, including cereberal hemorrages while at the controls (and yet still landed successfully!). This is not something you learn to do casually, but it is now taught as the primary G force resistance strategy, with an air bladder G suit being seen as the adjunct to this effort.
On top of the coordinated anti-G clenching a pilot in high G manuevers is doing, he is also working to keep his control inputs coordinated and within control effort limits. This is where fly-by-wire aircraft have important advantages over older systems of managing flight control surfaces. Fly-by-wire aircraft can be made "forgiving" of pilot control problems in high G maneveurs, by "sanity checking" algorithms in the software that interprets control inputs, and creates flight control surface actuator commands. So, if a pilot is failing to accurately center his joystick during control transitions, due to G forces, the plane can actually sense that, and compensate.

But to come back to the original question: My sense is, that with all the mental and physical effort associated with resisting Gs and staying mentally "ahead" of a high performance plane in high load manuveurs, there is a low probability of erections occuring spontaneously.
posted by paulsc at 2:00 PM on January 31, 2007

I was a fighter pilot in the Marines. I can say that I don't ever remember this happening to me in the jet, even when flying straight and level.

I am not sure if it is a mental or physiological thing, but there is just too much to worry about while pulling Gs (bombing/dogfighting) that I doubt I even would have noticed.
posted by bagels at 2:04 PM on January 31, 2007

just a semantic point, but is there really such thing as an "intentional" erection? I mean, is "intent" really ever involved?

I have certainly been in situations where i was happy to get one, but I wouldn't say it was created by my "intent" - it always just sort of happens, doesn't it?
posted by drjimmy11 at 2:26 PM on January 31, 2007

I have only done very few hours in an Extra 300 but holyshitno, erections certainly don't happen when the blood rushes out of your head. I was told to cramp my legs really really hard to prevent blacking out. you really work quite hard there to keep yourself alert and even though I don't know how erections work for you, I think it's safe to say that you would lose any under such circumstances.

press your flat hand really really hard onto your genitals. it's just uncomfortable (unless you're a german).
posted by krautland at 6:13 PM on January 31, 2007 [1 favorite]

just a semantic point, but is there really such thing as an "intentional" erection? I mean, is "intent" really ever involved?

I lose my erections the moment I lose my concentration. make me chuckle, giggle, laugh and it's back to square one. I'd say intentions are involved.
posted by krautland at 6:15 PM on January 31, 2007

just a semantic point, but is there really such thing as an "intentional" erection? I mean, is "intent" really ever involved?

It is by will alone that I set my... in motion.
posted by jimfl at 7:58 PM on January 31, 2007

Erections aren't caused by increases in lower body venous pressures. In order to get an erection, special arteries under nervous control have to dilate, allowing systolic-arterial-pressure blood to fill the cavernosa. When this happens, venous outflow from the cavernosa, normally quite adequate, is shut off because the expansion of the cavernosa collapses the outflow veins. It's a nice little system and if you didn't know better you might be moved, upon contemplation, to appreciate the intelligence of the design.

Venous blood pooling in the lower body might reduce penile outflow a little bit, but there's no commensurate increase in inflow as there would be during physiologic erection. Furthermore, the outflow veins are actually less likely to collapse as the pressure in them rises. So from a mechanistic or structural viewpoint, this is not likely to occur.

If the venous pressures start to near or exceed arterial systolic pressures, the pilot has much more serious things to worry about than his penis.
posted by ikkyu2 at 11:32 PM on January 31, 2007