One more approach and we were done for the day. We chose the RNAV 35 at Peter O. Knight Airport in Tampa, FL (KTPF) which takes us over the manatee viewing area over Apollo Beach.
My student reviewed the weather, loaded the approach into the GPS, and briefed the approach. All was going well until the controller issued the clearance "cleared direct HUMKI, maintain three thousand, cleared for the RNAV 35 approach".
The flight plan page was selected, HUMKI highlighted and the direct-to button was pressed. NAV was selected on the autopilot and we were on our way towards HUMKI for one turn in the hold which should position us for the inbound course, or that is what we though we where doing.
It was a typical fall morning in Tampa Bay, smooth cool air without a bump the entire flight. Relaxed and enjoying the wonderful views I thought to myself, boy this is going to be a great end to the day until I noticed something odd, two magenta letters MH next to HUMKI on my GPS.
"Why does it show we are holding at the missed approach point when we are just starting the approach?" I said with a perplexed tone. My student looked up at me from under his view limiting device with an even more confused expression indicating both of us did not realized what had happened.
It suddenly dawned on us that we had selected HUMKI on the flight plan but the wrong HUMKI. HUMKI is displayed twice, once as an initial approach fix and then as the holding point for the missed approach. We had selected the later and were navigating towards our missed approach point.
We quickly reactivated the approach and then began flying direct-to HUMKI for one turn in the hold to realigning ourselves for the inbound course. To my delight a magenta IA was after the waypoint HUMKI and the word hold was displayed in the flight plan. Proceeding towards the initial approach fix opposed to the missed approach holding point defined by HUMKI I began to reflect on what went wrong and why.
When preparing for the approach either activate the approach or proceed direct-to a fix on the approach. Using the direct-to a fix on the approach will automatically activate the approach in the G430W.
Before pressing the direct button it is good idea to take a moment and verify you have selected the correct point along the approach. This is especially important when the fix defines multiple points along the approach. In our case HUMKI is the Intermediate Fix, Final Approach Fix, And the Missed Approach Holding Fix.
As is true with most buttons in the aircraft it is best to take your time when selecting and pressing any switch or button on the GPS. Next time you hit direct-to make sure you look at the fix and verify that you have entered it properly. Most airline operating procedures require both pilots to verify any fix prior to entering it into the navigation equipment. Maybe we should adopt this methodology in the aircraft we fly. Verbally say to yourself "selected" and "verified" each time you make a change to your navigation system and you will have less entry errors while flying.