I've looked at Drop Troops and their Grav Chutes and I just don't agree with the use of the Operate (Aeronautica) skill. This is the skill at flying the Valkyrie - which no Guardsman should have (let the Navy do the flying). Sure, true Jump Packs use the Operate (Aeronautica) skill, but those allow actual flight (for a short time) while the Grav Chute just lets you make a controlled fall. Way back in DH Grav Chutes used Acrobatics as the skill to land. I think that this is a better option.
I intend to replace Operate (Aeronautica) with Acrobatics in the description of the Grav Chute and to switch the starting skill for Drop Troops from Operate (Aeronautica) to Acrobatics. In addition to being more fitting, Acrobatics is likely to be a more useful skill to a Guardsman since they are not supposed to know how to fly aircraft and their opportunities for doing so are likely going to be very rare in any event.