Bearfoot Posted August 24, 2019 Posted August 24, 2019 (edited) Ok, so I've got her trimmed and stable at 800ft and 350 knots with wing fully swept back, looking good flying past the carrier on port. Wait a bit, and then execute the break: throttle to idle, speed brakes out, kick in a bit of left rudder and initiate a roll. .... and find myself CLIMBING --- gaining altitude rapidly --- as I turn, with the VSI spiking and the flight path marker (FPM) going high above the horizon. Wut? Everything I've read, and my experience with that "bad-habit-builder" F/A-18, leads me to expect that I would actually lose altitude and would need to in fact have added in some power before the turn to compensate. But this is not happening here! Ok, so I try some more left rudder to bring it under the control. But here is where things get weirder (or rather, shows how much a bigger idiot I am). The more left rudder I apply, (a) the more the W marker drops [as expected]; BUT (b) the higher above the horizon the FPM climbs and sure enough, the VSI/rate-of-climb goes up and there is rapid altitude again. Wut? I can see failing to coordinate the turn due to not year learning the correct amount of rudder, but I do not understand the correction direction having the OPPOSITE effect! The more rudder in the direction of the turn I put, I would expect the more the plane to "cut into" the turn, nose dropping and less climb. Ok, let's try some top rudder ... and again, wut?? The FPM drops down even as the WW goes up. So that brings the crazy climb dowm though still have to kick in some pitch forward to control the turn. Spent the last few hours reading the Internets, am familiar (at least in theory) with proverse/advere yaw characteristics having watched the Jabbers video etc., understand coordinated turns (having been simming for, let's just say a very long time now) and am still confused! ----------------- (1) Why am I climbing in a break turn with wings fully swept, throttle idle, speed brakes out, flaps up and gears up, when it seems that almost everyone else is losing altitude? (2) Why does rudder input in the same direction as the turn cause INCREASE the rate of climb, with the WW and FPM separating (the WW drops but my FPM goes above the horizon)? With more rudder input making the situation worse? (3) Why does top rudder have the opposite effect, causing the FPM to drop below the horizon even as the WW goes up? :helpsmilie: Edited August 24, 2019 by Bearfoot
Cab Posted August 24, 2019 Posted August 24, 2019 Adjust your angle of bank to maintain altitude in the break turn. I.e. Increase your AOB if you’re climbing, and decrease AOB if you are descending.
Eagle7907 Posted August 25, 2019 Posted August 25, 2019 Following. I too have stability issues for the break. I'm able to trap, but man is it ugly! Win 10, AMD FX9590/water cooled, 32GB RAM, 250GB SSD system, 1TB SSD (DCS installed), 2TB HD, Warthog HOTAS, MFG rudders, Track IR 5, LG Ultrawide, Logitech Speakers w/sub, Fans, Case, cell phone, wallet, keys.....printer
Victory205 Posted August 25, 2019 Posted August 25, 2019 Your rudder inputs are causing Sideslip, which is the behavior displayed on the HUD symbology. Sideslip isn’t a primary means of managing altitude. Roll with lateral stick and a little coordinated rudder, which is neutralized when the lateral stick is removed to stop the roll. The rest is using angle of bank to position the lift vector to control climb or descent. Fly Pretty, anyone can Fly Safe.
Bearfoot Posted August 25, 2019 Author Posted August 25, 2019 Adjust your angle of bank to maintain altitude in the break turn. I.e. Increase your AOB if you’re climbing, and decrease AOB if you are descending. Your rudder inputs are causing Sideslip, which is the behavior displayed on the HUD symbology. Sideslip isn’t a primary means of managing altitude. Roll with lateral stick and a little coordinated rudder, which is neutralized when the lateral stick is removed to stop the roll. The rest is using angle of bank to position the lift vector to control climb or descent. AOB to control climb by position of lift vector: golden. Thank you both for the advice/insight. Weirdly (and stupidly, it seems), I've always used some rudder to position my nose above (top rudder) or below (rudder in direction of bank) to manage climb during a turn --- with the higher the nose gets pointed above the horizon due to rudder-induced yaw the greater the rate of climb, and, conversely, the lower the nose below the horizon the greater the rate of descent. The sideslip was a necessary evil. It's worked well enough in simulations of other aircraft, particularly the WW2 birds. But your responses have provided some welcome corrective lenses. It's like blinders have been removed from my eyes letting me see an ugly habit that I now know I should work on to be fixed. Thanks again!
Cab Posted August 25, 2019 Posted August 25, 2019 That was the nicest, most complete "thank you" I have ever seen. Thanks for that.
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