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Old May 21, 2011, 12:02 PM
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Joined Jul 2009
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MaladroitFL,

The maneuvers I mentioned were simply routine training and/or combat maneuvers for WWII fighter pilots. They are completely scale when performed correctly, and they are not in any way considered to be 3D flying. To make them look scale, you need enough speed & power to carry-through the maneuvers. A tight, lopsided loop does not look scale. A nice, big round loop does look scale. A hammerhead in which the plane only goes vertical for a few fuselage-lengths before running out of airspeed does not look scale. A hammerhead in which the plane does a graceful, extended vertical climb before pivoting & coming back 'downhill' does look scale. These little foamies have a ton of drag, and they lack the momentum of the larger-scale models. This makes it more difficult to execute graceful, scale-looking aerobatic maneuvers. Lacking momentum, speed and thrust must be used in the proper combination to make the maneuvers look scale with a UM ship.

When a full-scale F4U does a loop from war-emergency power speeds over 400 MPH, the loop is thousands of feet in diameter. When it does a zoom-climb @ war-emergency power following a WOT diving pass, it will climb nearly straight up for a few miles.

When the pilot executes a hammerhead to reverse a situation where the enemy is on his six, the plane would be balls-to-the-wall...ripping through the sky at well over 400 MPH....the big, unmuffled R-2800 at red-line, screaming as loud as a Top-Fueler at the big-end of the track...the prop shrieking as the tips go supersonic. The pilot hauls the stick back and rockets straight up for a couple of miles before slamming in full-rudder, pivoting on the yaw-axis, and then bringing his guns to bear on his enemy - engine still screaming at full war-emergency power.

3D flight is a type of flying in which model aircraft have a thrust-to-weight greater than 1:1 (typically 1.5:1 or more), large control surfaces with extreme throws, low weight compared to other models of same size and relatively low wing loadings. These elements allow for spectacular aerobatics such as hovering, 'harriers', torque rolling, blenders, rolling circles, and more, maneuvers that are performed below the stall speed of the model. The type of flying could be referred to as 'on the prop' as opposed to 'on the wing', which would describe more conventional flight patterns that make more use of the lifting surfaces of the plane.

Regarding bigger batteries & motor life - those of us who have been flying these UM ships since HH released the original Sukhoi have found that there is no correlation between motor longevity & battery capacity. Of course, a higher c-rating cannot shorten the life of the motor, as a higher-c battery simply guarantees that the motor receives the proper voltage. This reduces current, which makes the motor run cooler. If anything, a higher-c battery will extend motor life, since the higher voltage will cause the motor to run cooler at a given power setting. You make the assumption that most pilots fly @ WOT, or nearly so. Aside from takeoffs, certain power maneuvers, or during windy conditions, I rarely go beyond 75% throttle on my micros. With the XP, I usually cruise at 50-60% throttle, and only go to WOT for vertical uplines. With the SP motor/5043/Hyp 240, my Champ only requires 50% throttle on takeoff, and it cruises @ 25% throttle. It climbs briskly @ 60% throttle. The reserve power is for short-field takeoffs when she's carrying the 15g camera, and for windy conditions. Regarding the F4U - with the 5043 & Hyp 180, ~50% throttle provides a scale cruising speed - with enough reserve to gracefully perform the scale dogfighting maneuvers I mentioned.

I have two original Sukhois, three XPs, two Beasts, a Champ, Mossie, F4U, mSR, and mCP X. I've been flying with Hyperion UM cells since they were first released. A number of the P-51 motored planes have 200+ flights, and the motors are still going strong. According to static RPM testing, the power is down maybe 5%. On the other hand, I have had P-51 style motors fail before they made it to the runway, or fail after the first flight.

Motor variability is the primary contributor to differences in motor longevity. Any difference that could possibly be attributed to battery capacity or c-rating would be completely below the statistical noise caused by the large variability we have seen with these motors over the past few years.

Joel
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