Jim P
Well Known Member
I'm not sure if anyone has actually tested this corner of the RV-7 flight envelope, and I sure hadn't until today, and subsequently learned something new!
I was out for a short flight today, cleared out from under the Puget Sound overcast and found a nice big blue hole south of Enumclaw (south east of Seattle) to climb up and do some light acro at about 4000?. I lined up for a nice easy barrel roll to the left, got the nose up and let myself fall out of the maneuver. I recovered with further roll to the left with nose down about 20 degrees, which in itself isn't a big deal. I have a coolie hat trim switch on the top of the stick, and sometime during the recovery, I inadvertently pushed the trim full nose down. Speed built up relatively quickly to about 220 MPH and with the nose down, high speed and full nose down trim, the stick forces were very high! Stick forces were high enough to actually give an impression that something could be jammed, but that wasn?t the case. This all happened fairly quickly and as soon as I noted the high airspeed, throttle went to idle and prop forward to assist in getting slowed down, all while pulling the stick. I was trying not to pull too hard in order to keep from over-G condition, but pull hard enough to get some airspeed bled off, arrest the dive, and avoid a close encounter with some big trees. I finally got the airplane returned to level from the nose down pitch around 1500? or so, and then I noticed the trim indicator in the full down position, which I was happy to see, and ruled out some sort of linkage issue. The airplane was never out of limits, but the trim condition made a simple recovery into something a bit more difficult.
In short, I?m not sure I?d want to see an airspeed any higher with full nose down trim, or one might not be able to apply enough back pressure to effect a recovery. For those with trim on the stick, just be aware something like this can happen when you least expect it.
I was out for a short flight today, cleared out from under the Puget Sound overcast and found a nice big blue hole south of Enumclaw (south east of Seattle) to climb up and do some light acro at about 4000?. I lined up for a nice easy barrel roll to the left, got the nose up and let myself fall out of the maneuver. I recovered with further roll to the left with nose down about 20 degrees, which in itself isn't a big deal. I have a coolie hat trim switch on the top of the stick, and sometime during the recovery, I inadvertently pushed the trim full nose down. Speed built up relatively quickly to about 220 MPH and with the nose down, high speed and full nose down trim, the stick forces were very high! Stick forces were high enough to actually give an impression that something could be jammed, but that wasn?t the case. This all happened fairly quickly and as soon as I noted the high airspeed, throttle went to idle and prop forward to assist in getting slowed down, all while pulling the stick. I was trying not to pull too hard in order to keep from over-G condition, but pull hard enough to get some airspeed bled off, arrest the dive, and avoid a close encounter with some big trees. I finally got the airplane returned to level from the nose down pitch around 1500? or so, and then I noticed the trim indicator in the full down position, which I was happy to see, and ruled out some sort of linkage issue. The airplane was never out of limits, but the trim condition made a simple recovery into something a bit more difficult.
In short, I?m not sure I?d want to see an airspeed any higher with full nose down trim, or one might not be able to apply enough back pressure to effect a recovery. For those with trim on the stick, just be aware something like this can happen when you least expect it.