FanaticFringe AlpineTrail Pack

A v-frame or any internal frame is not dependent on a hipbelt to transfer a load or at least some of the load to the back. The hips are not the only place that frames transfer loads to. When the shoulder pads are tightened on a beltless pack, the frame arcs under tension against the back – when you force a relatively rigid structure against the back, the force of the resistence holds it in place. This works better if the pack is tall enough to at least reach the height of the shoulders. This cannot happen if there is not a ‘Frame’ that connects the upper end of the shoulder pad to the lower end of the shoulder pad strap. It is simple mechanics and the same general mechanics are what projects an arrow from a bow. To get this effect with a light internal frame, or even a more heavy duty one, it may be necessary to straighten the frame a little so that it has more potential to flex against the back. A rolled pad is more than likely already straight and there would be ways to stiffen it like rolling it more tightly.

Sternum straps can focus some of this tension to the chest and keep the pack from pulling the shoulders back.

What he said. I can definitely notice a difference between v-frame and empty sack, with or without hip belt. Just grab a pack and try it out and I think you’ll feel the difference. Whether you like it or not is another story.
-Mark

Mr. McHale,

very clear explanation. understood. guess i was thinking too one-dimensionally. there sure is a lot of engineering involved in suspension design – much more than i understand. your explanation sounds somewhat similar to an explanation Dr. Caffin recently gave me of a framed pack he designed and how it transfers load even if he doesn’t use the hipbelt. many thanks for taking the time to reply.

Mark,

i’ll have to give it a go. can’t use my Breeze pack though as, quite a while ago, i added a 2oz hipbelt to it. guess, i could try it without cinching the belt. thanks for taking the time to reply and give me the benefit of your personal experience.

I think you can feel it even with the belt hanging there. My experience is with the Golite Jam. A lot of times I’ll just leave the hipbelt uncinched and flopping around just for variety. On longer trips, I can’t always fit the pad inside with a new load of food. Usually the next day, with the pad inside I can notice a difference in the way it hangs or hefts [slight weight difference aside]. V-frame-less does feel a bit more ‘saggy’. It’s kind of neat. You wouldn’t figure a few ounces of foam could make such a difference.

-Mark