March 26, 2014 at 6:28 pm #84950
I recently purchased a 1981 Cessna 414A with RAM winglets. When this aircraft is in level flight with the ball centered, the left aileron trails about a half inch up and the right is a quarter inch down. It also requires a bit of left rudder trim. My maintenance shop has leveled the airplane, re-set all the rigging to original specifications and verified the ball is level in the panel. I’ve been told there is nothing else I can do, yet these trim abnormalities assail my fastidious nature, as I would much prefer seeing a straight line from the flaps to the ailerons. This airplane has never been in an accident (at least according to the logbooks) and appears to have a clean history.
I spoke with Tony Saxton and was told that Cessna allowed up to a half-inch deflection in aileron correction from the factory. However, others with whom I have spoken say this is not normal. I also understand there is no way to adjust the wing-to-fuselage joint as there is on other aircraft.
The only other culprit I can think of would be the winglets. Perhaps they were installed incorrectly? I called RAM and explained the situation to a person “in-the-know” there. He said the winglets were manufactured and installed by RAM to exacting standards and it is extremely doubtful they were mounted incorrectly.
1. Is there anything else I can do to straighten this airplane in flight?
2. How much airspeed penalty am I paying in knots to have this condition?
3. If the winglets are the culprit then is their benefit obfuscated by their own improper installation?
This is really frustrating me. Any suggestions you guys could come up with would be much appreciated.
JohnMarch 26, 2014 at 7:01 pm #104260
Have you checked your flaps and gear doors? Are they fully closed and tight when retracted?
A common, and incorrect, method of “solving” this problem on Aztecs was to drop one of the flaps slightly. Made me crazy.
My 340 flies slightly right wing low with the ball centered and ailerons level. I doubt if I’ll chase it, but it got me thinking about lateral weight differences between the right and left side of the longitudinal axis.
On the Left, I have Keith AC, aircraft battery, voltage regulators, electrical and circuit breakers, AC power inverter, electric HSI, full pilots instrumentation, Garmin remote mounted radios, landing gear motor and gear box, aircraft cabin door…
On the right, I have a roll servo, Janitrol heater, remote mounted radar altimeter, emergency exit… and that’s about it.
I would tend to think if anything, my 340 would fly slightly left wing low.March 26, 2014 at 7:07 pm #104261
Oh yes, we’ve checked the flaps and gear doors. My maintenance shop actually extended the right wing flap with one turn of the rod with no effect. When I get it back in the shop I’m going to have him extended it another turn or so.March 26, 2014 at 7:50 pm #104262
I had a 61 310-F that did the samething. Long story short that plane had a hard landing. The right wing engine beam was slightly lower then the left wing. I noticed this by standing in front of the plane about 10 yards back that the right spinner was slightly lower then the left. Give that a try.March 26, 2014 at 9:21 pm #104267
I think it is normal. When in level flight the ailerons will not be perfectly aligned with the wing. When flying there will always be some trim required to fly straight and level. You never have exact fuel, or oil on each side, your weight will never be exactly equal and the propulsion from your props are never perfectly matched to the plane’s centerline.March 26, 2014 at 10:03 pm #104268
I notice something this on every airplane I have flown.
I think you have to relax and take it like something normal.
What causes it? I do not know, but my guess is something about construction and power differential.March 26, 2014 at 10:20 pm #104271
(Said with a sigh of resignation…)
That’s what everybody at the airport Table of Knowledge keeps telling me…it’s normal. Maybe it is. You think I’m losing any speed? It seems to get book numbers with winglets.March 26, 2014 at 11:50 pm #104272
If you are getting book numbers you are ahead of the game.March 27, 2014 at 12:17 am #104273
Every airplane is different. Remember that while these were built with jigs, they were hand built many years ago. Some just fly a bit different. My 310 flies with the ailerons perfect. The previous owner bought a RAM T310R that does 225-240 KTAS @ FL190-200 (IOW – fast) but has a similar aileron issue to what you describe.
If you’re making book numbers, I would be happy and move on with life. Clearly your plane’s faults are minimal if you can make book.
But I agree, it would drive me nuts, too.March 27, 2014 at 12:36 am #104278rtoweParticipant
We have the same issue in the Crusader…I recently weighed the airplane and of course, the left side weighs 50 lbs more than the right due to the battery in the left nacelle. I have the aileron trimmed a little to the right to compensate, ball is in the center, it’s just the way it is and it does book speeds…March 27, 2014 at 2:49 am #104280pmcnameeParticipant
For any given weight and CG of an airplane the least total drag is obtained when the the vertical component of lift is perpendicular to the center of the earth. Therefore, in cruise we want the wings perfectly level.
Balance the fuel between the wings as required. Set equal power on both engines. Engage Autopilot in “Heading hold”. Use RUDDER TRIM to level the wing. Take your time as you look at the wing tips below the horizon being perfectly level. Turn Autopilot off and use AILERON TRIM to stop any rolling tendencies. There, the airplane is in trim. If you have a Cessna autopilot, engage autopilot. Use roll knob out of detent to put autopilot in roll mode (not HDG). Use autopilot roll trim to again roll wings perfectly level. Now the autopilot is also in trim.
The control surfaces may not be centered, but the airplane is flying straight. The ball might not be centered (it could just be wrong).
There are a thousand reasons for the airplane not to be able to make book speed. It is almost impossible to better book speeds because the certification airplane was flown at the optimized configuration for speed.
PatMarch 27, 2014 at 4:54 am #104289quote TDUPUIS:
I’d bet your previous owner has an inaccurate airspeed indicator.March 28, 2014 at 1:59 am #104325
1981 414A no winglets 🙁
I have moderate changes in rudder trim in different phases of flight (TO, cruise). I do have to adjust the aileron trim once in cruise phase but the rudder trim is always has the most impact on straight and level flight.
I don’t believe the aileron trim or position would have a demonstrable impact on performance however on 400 series twins, a poorly trimmed large rudder deflecting all that air probably would.March 28, 2014 at 3:22 am #104330quote SGERBER:
RAM IV T310R, flown at high power, ROP. Burns about as much fuel as your 421. We were doing 225 on an ISA+25C day. In the cold winter, it’ll get that 235-240 range.March 29, 2014 at 2:26 pm #104350
I just made a trip with a buddy of mine who owns a Citation 501SP. So I’m sitting in the back enjoying a cool beverage when I happen to look at his left aileron. Guess what, his left aileron trailed a half inch down and his right was about even. Coincidentally his airplane is a 1981 model just like my Chancellor. Maybe Cessna’s quality control guy back in 1981 was a little lax.
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