Hands Off Flying, Part II
By Hank Gibson, CFI, CFII, MEI
Scenario 1: Starting Simple
Jeff had just purchased his new Cessna Skylane, complete with a G1000 and a KAP 140 autopilot. Jeff was not completely comfortable with a G1000, but he had decided to splurge and go for the G1000, 182T NAV III model with a KAP 140 autopilot. He had scheduled some lessons for the following week to become more proficient.
Jeff brought his friend, Nate, along with him to help him fly the airplane home. The two men were based out of Tulsa, Oklahoma, and Jeff bought the plane in Wichita Falls, Texas. Nate owned a G1000 aircraft himself, so he seemed like a logical choice to bring along for Jeff.
The morning dawned bright and clear, a perfect day to fly. Jeff and Nate took off at half past 7 in the morning, climbing into a beautiful, November sky. As they climbed up to 8,000 feet, Jeff showered Nate with questions about the different soft keys, the procedure button, setting up flight plans and so on. Nate was very understanding and patient with Jeff’s questions and was happy to be of help.
After leveling off, Jeff’s eyes fell upon the autopilot. “How does that thing work?” he asked. Here was a problem for Nate, since the Cessna 400 he owned had a Garmin autopilot in it, he was not all that familiar with the KAP 140. “Well, let’s turn it on and play around with it,” he said. So, Jeff pushed the AP button and the autopilot flashed to life. Jeff pushed the HDG button, thinking the autopilot would naturally hold the heading the airplane was currently on. As soon as the HDG flashed active, the plane started turning to the left. Full of alarm, Jeff grabbed the yoke and fought the autopilot’s efforts to turn the airplane. He was flying on an IFR clearance, so a deviation from the route could be a big deal.
Nate, figuring out what was going on, looked at the heading bug on the PFD. It was set for a heading of 240, even though they had been flying 035. Jeff, meanwhile, was cursing the autopilot, wrestling the controls with all his might. Nate reached over and pressed the AP button to turn it off. “Holy cow. Thanks for turning that thing off. It was going crazy!” exclaimed Jeff, while catching his breath.
“Well, not exactly,” replied Nate. “See where your heading bug is set? I’m pretty sure when you turn the heading mode on, the autopilot will turn the airplane to wherever the heading bug is set.”
“Really? Oh. I thought it was defective or something. Huh, that actually makes sense. I think we’ll leave it off for now until I know how to use it better.”
Lesson: Before activating heading mode on the KAP 140, always make sure the heading bug is set properly for the desired heading. The autopilot in HDG mode always turns to the heading the bug is set for.
Scenario 2: NAV Nightmare
Don was happily puffing along in his 172SP NAV III on his long instrument cross country. He and his instructor, Tony, were going to Waco, San Marcos (TX), Austin, then back to Waco. They had completed most of the trip and were headed back to Waco from Austin. Tony had been adamant thus far that Don couldn’t use the autopilot; he had to hand fly all of it. Tony said it made Don a better pilot.
On this leg, though, Tony relented and allowed Don to turn on his KAP 140 autopilot. The two guys started chatting after setting the autopilot on NAV mode to follow the flight plan Don had set in the G1000. The two lost themselves in conversation about the Baylor football team, debating if they could win out and make a good bowl game or not this year. Tony realized he should be doing a little more instructing and asked a very instructor-like question. “Hey, let’s see what radial off the Temple VOR we are on.”
So, Don tuned in the Temple VOR, identified it, and pressed the CDI button to change from GPS to VOR. He centered the VOR needle and all of a sudden the plane started turning left. They were on the 150 radial, but the plane was not continuing to hold the flight plan course from the GPS. For whatever reason, it was starting to follow the VOR needle. “Is that supposed to happen?” asked Don as he stared at his PFD.
Tony shook the cobwebs out of his head and pressed the CDI button twice more to bring the GPS needle back up on the HSI. “Now that I think about it, yes, the NAV mode on the autopilot follows whatever is set in on the HSI. APCH mode does the same thing, it just makes the autopilot more sensitive in approach mode.”
Lesson: When the GPS is in NAV or APCH mode, it will automatically track whatever navigational device is set as the active CDI function on the HSI. Be sure to set the CDI properly before activating NAV or APCH mode.
A few closing tips for the KAP 140. To set the altimeter on the autopilot, press the BARO button. Always make sure the altimeter is set properly or it will not hold the proper altitude.
When descending or climbing in VS mode, always press the ARM button to arm the altitude to level off at. Otherwise, the autopilot will continue descending right into the ground or climbing until the service ceiling is reached.
Lastly, whenever a dual axis autopilot is installed, the pilot still controls the rudder. Most importantly, don’t become overly reliant on the autopilot!