Bob,
I had understood a human could sustain 9G (according to a Wiki I read) but was
not sure how long they meant by sustain. If I go with the 3
minute turn and 0.33G/thurst, the fighter Jocks might have to sustain
6Gs several times (like anytime they go foot to the firewall) but they are (as
you say) in couches and G suits. I figured if we can manage 9Gs for a minute
or two, we can manage 6Gs with some help (unhappily, I'll warrant) for longer
periods. Keeping the ship to 2Gs (for Thrust 6) means humans can move
(carefully) and work (if need be) when the ship is under power. More common
thrust 4 means 1.33 G. Not pleasant, but the medics and damage control parties
can work here.
Letting the fighters hit higher than 6Gs at times (or even the ships going
over 2 Gs average thrust for a turn with engine
redlining/emergency thrust) is probably feasible, but I want to keep
the norms on the lower end. I think 2Gs is probably enough to be doing damage
control even in a powered exoskeleton..
Tomb
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http://mail.csua.berkeley.edu:8080/mailman/listinfo/gzg-lIf Thrust 6 is
2Gs, Fighters moving at 12 (accel/decel) would only be at
4Gs. Reasonable. :-)
Mk
> On Tue, Jan 19, 2010 at 6:20 PM, Tom B <kaladorn@gmail.com> wrote:
> Bob,
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http://mail.csua.berkeley.edu:8080/mailman/listinfo/gzg-lOn Tue, Jan 19,
> 2010 at 5:20 PM, Tom B <kaladorn@gmail.com> wrote:
> Bob,
G loads are tiring. Formula 1 drivers hit 5 and 6 gs throughout a race. The
car only hits equilibrium at top speed. The rest of the time it's under some
sort of g load, from 1.5 gs to 6. F1 drivers have to be *very* well
conditioned, and even then it's tiring as all get out.
It's more than just what your muscles can take. Under breaking the driver's
lungs want to press against their ribs and force them to exhale. I'm not sure
even a g suit does anything about that: just regular breathing is hard.
Here's a YouTube video about F1 g loads. It's quite interesting:
http://www.youtube.com/watch?v=EMloWN-AZcw
Just how horrible would it be to take trauma damage in combat while the craft
continued to pull 5 gs?
Personally, I think to handle high g loads for any length of time (F1 races
are about 2 hours but F1 drivers don't suffer 5 gs constantly for 2 hours in a
row) they'll need more than a g suit.
> Letting the fighters hit higher than 6Gs at times (or even the ships
I think 2 gs is more reasonable.
Allan spake thus:
G loads are tiring. Formula 1 drivers hit 5 and 6 gs throughout a race. The
car only hits equilibrium at top speed. The rest of the time it's under some
sort of g load, from 1.5 gs to 6. F1 drivers have to be *very* well
conditioned, and even then it's tiring as all get out.
It's more than just what your muscles can take. Under breaking the driver's
lungs want to press against their ribs and force them to exhale. I'm not sure
even a g suit does anything about that: just regular breathing is hard.
[Tomb] I'm not sure there is any quantifiable difference between
acceleration/deceleration stresses and cornering stresses (heavy
lateral G loads there) in F1 and the same sorts of stresses in (for instance)
fighter planes. They have afterburners, arrestor cable
landings, and very heavy G loads during manouvers. G-suits help the
guys in the planes, I see no reason to believe that they would not help F1
drivers to some extent.
Just how horrible would it be to take trauma damage in combat while the craft
continued to pull 5 gs?
[Tomb] Well, this is not such a big deal in fighters. Fighters are
either fine or dead. If you take any notable hit in a fighter, they notify
your next of kin. Larger ships doing those kinds of Gs and taking serious
kinetic or beam damage would have people trying to deal with casualties,
system failures and damage, structural damage, hull breaches, etc. all while
under 5 Gs. I can't see that improving any casualties chance of surviving or
even being manageable without
anti-gravity somehow. You'd have to take off G-load.
> Tom B wrote:
fighter planes. They have afterburners, arrestor cable landings, and
very heavy G loads during manouvers. G-suits help the guys in the
planes, I see no reason to believe that they would not help F1 drivers to some
extent.
> [quoted text omitted]
I'm a bit dubious regarding the use of g-suits in F1, mostly because I
don't know how they'd work against lateral accelerations -- and I wonder
if anyone else does. The big difference between fighter g loads and F1 g's is
in the direction of the acceleration. In the examples you give above, Tom,
there are AB and trap loads, which are basically
fore-and-aft (longitudinal) loads, to which could be added catapult
launches, probably the greatest of the lot; and there are turning loads,
which are normal accelerations. These are in different directions (x and
z respectively, in terms of body axes) and, AFAIK, g-suits don't do much
against the longitudinal cases -- but they don't have to, because the
highest loads (5.5 g on a cat launch) don't last very long, and the
sustained loads (AB accel) aren't that great -- if you can achieve 1 g
and hold it for any length of time, you're doing well. The normal load
-- what we normally think of as g's pulled -- are what a g-suit,
together with straining manoeuvres, is intended to relieve, but you don't get
them in an F1 car in the same way (or if you do, you're probably about to
crash because you've left the track and are most
likely in mid-air). The highest g loads in F1 are the lateral cornering
loads, which are in the y direction in terms of body axes, and you don't
get them much in flight; they would require sustained, heavy sideslip and,
with the exception of a few experimental types, that's not something that's
achieved or wanted in an aircraft.
Of course, I'm no aviation medic, so maybe I'm wrong. Anyone know for sure?
Phil
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http://mail.csua.berkeley.edu:8080/mailman/listinfo/gzg-lOn Wed, Jan 20,
2010 at 11:33 AM, Phillip Atcliffe <atcliffe@ntlworld.com>wrote:
> [quoted text omitted]
I'm a bit dubious regarding the use of g-suits in F1, mostly because I
don't
> know how they'd work against lateral accelerations -- and I wonder if
That was part of my point.
Tom misses the main thrust of my argument (which, I admit, I didn't make
forefully). F1 drivers are under g loads for two hours and it's exhausting. In
fact, they are *not* under g loads *constantly *for two hours, though they are
under *some* g loads for most of that time. (The amount differs per track, I
would think the Yas Marina circuit is one of the easier ones, as it has the
longest straight in F1.)
Dogfights just don't last 2 hours. The length of time under g load is an
important consideration. That's why I brought up F1. F1 drivers are
conditioned athletes, and they're tired after 2 hours of racing. I can't think
of anyone else under those types of g loads for as long.
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you are under G loads you will be tired after 2 hours of high adrenaline
levels brought on by combat stress. I imagine 2 hours sitting in a bunker
being shelled is very stressful and tiring even if you are not moving.
I don't know what the impact would be of trying to handle multi G
accelerations accross combinations of the thress axis at once. I have visions
of every unsecured item bouncing up and down as the accelerations com on and
off.