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gizzard

weight and balance.................

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Just read an announcement that the helicopter that crashed August, 08, in california, doing firefighting activities, was nearly 30% over gross allowable..........The crash killed a number of firefighters and the flight crew.. Seems as if the operator had intentionally, apparently, gave false information about the weight and other performance data of the S-61, which is, i think, a civilian version of the H-3?

I reckon that just shows to go ya how important that weight and balance stuff really is, especially when you are operating near the aircraft limits. Maybe that's why us loadies flew with the plane, as a sort of guarantee.

Are any of you aware of any similar, if not nearly as disasterous, situations involving the 130?

giz

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Only thing I know where it could have been was in '76 (?), 32nd TAS, leaving out of Kelly AFB in an E model, full fuel, 5 crew members, 2 fuel specialists, and 2 of the large fuel bladders full of fuel, heading to southern Mexico on a humanitarian mission. Not exactly sure what we weighed (don't remember how much fuel those big things held) but if we had lost an engine, I'm sure we would have been a smoking hole in the ground. I had the bleeds closed until we got some altitude below us, zooming at 500 FPM.

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I remember four, five times right at 155K, real tight on %Mac, once, in Turkey, orginally was about 158K, downloaded some gas and away we went........How does the balance limits work on a helicopter????? Scary thing is how do you know the weights, and for that matter, the moment arms are accurate???????

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First, I don't know what the rules are for fire fighting, but I know crop dusters USED to be able to take off at 30% over gross. I don't know if they can AND this is what I've been told - never been a crop duster, but have lots of friends who have. Does this apply to helos? No idea.

What I've found interesting is that here on civvie street, I, as the FO, do the W&B and it's not a Form F, nor anything like it. It's a spider diagram and plotting sort of method. My point? There's more than one way to skin a cat - no telling how different outfits operate the 'same' aircraft and still comply with the FAA...

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The Form F ALWAYS said that we were under 155K on the E model. On rotations we were much heavier than that. Also the FE's I flew with would always add a few thouand pounds to the weight I would give them to compute take off data.

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The true maximum on an E model was or is 175K, flying ABCCC out of Udorn we were damn close to that with 62k fuel and a capsule that weighted 20k plus, we would use all the runway for those 5PM lauches. The heaviest I remember for TO was 179K it took forever to get airborne

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The true maximum on an E model was or is 175K, flying ABCCC out of Udorn we were damn close to that with 62k fuel and a capsule that weighted 20k plus, we would use all the runway for those 5PM lauches. The heaviest I remember for TO was 179K it took forever to get airborne

Hey check/set, weren't the normal trash-haulers limited, at least on paper, to 155K? Wonder why the difference??I know that I am quite sure,as 0495 said, we often tokk off heavier. Depending where it was, I MAY be able to remember sometimes using a verbal "Form F", knowing full well that we were over the 155K, but the whole crew knew it planned for it, and hoped like hell we got off okay.

I can remember checkin' the cg's though. If I remeber right, didn't the charts for CG limits go above 155K?????

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155K is the normal maximum weight. 175K is the emergency/wartime maximum gross weight.

I've taken off heavier to make a landing weight of 175K... ;)

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155K is the normal maximum weight. 175K is the emergency/wartime maximum gross weight.

I've taken off heavier to make a landing weight of 175K... ;)

Okay, somewhere in my feeble mind I do remember something like that, now.......just don't ever recall actually applying it....I wonder what the absolute max take weight of an E-model would have been. If I remember right weren't there landing limits as well, and also, never got this really explained to me, a thing called limiting wing fuel????

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Wing limiting fuel was calculated based on cargo load, the idea was to limit the amount of wing flex, the heavier the payload the more fuel we needed to have to keep wing from bending up and over-stressing the wing.

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If I remember right weren't there landing limits as well

Really the Herk did have landing limits but they were expressed as maximum landing rate (FPM), really heavy you were restricted to 300 fpm.

Many a time I would give a pilot a told card and tell him the weight was 155K BUT IT WOULD FLY MORE LIKE A WEIGHT OF 170K or whatever real weight we were at (wink wink)

The worst overload I ever see was at Kamis Al Rasheed (I think that were we were) we took the entire 12k of runway to get off the ground an were lucky that the ground dropped away from us as that's the only way we could get a climb rate LOL

Running the climb rate charts backwards (had to use a pencil to extrapolate the lines in the chart since they didn't go far enough to match our climb rate) and we came up with a weight of 200K +- !!(dont really remember which chart it was, its been too many years since I've seen a -1-1)

Army had and probably still does weight the equipment empty then after weighing they load it up with their gear so your load out figures are nothing like the actual weights.

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I remember four, five times right at 155K, real tight on %Mac, once, in Turkey, orginally was about 158K, downloaded some gas and away we went........How does the balance limits work on a helicopter????? Scary thing is how do you know the weights, and for that matter, the moment arms are accurate???????

I can't think with those high numbers, Our C-13O-As were limited to 124,200 lbs gross TO, landing gear restrictions (if my memory is correct).

Bob M

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Seems to me that on every model revision, A/124k to B/135k (aux tanks) to E/155k (ext tanks), the GW went about the amount the fuel load was increased. Not sure if that was how intended or just a coincidence.

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