Narrative:

On an IFR flight plan from ZZZ to ZZZ1. My original destination was to be ZZZ2; but I chose ZZZ1 due to weather. While in flight I monitored the weather radar to see if it would have been possible to get through to ZZZ2. Radar results were looking positive and I also heard VFR traffic requesting flight following [in a location] which would have been across my desired flight path. I chose to cancel IFR and continue VFR to ZZZ2 with flight following. Visual conditions were clear and I would turn back if I didn't like what I saw. I selected direct to ZZZ2 from my present position which took me directly over four towers referenced above. [Approach] asked confirmation that I had the towers in my view; which I did. At the time; I was at 3;100 feet which would not have been sufficient. My on-screen terrain guidance showed red and I increased altitude to 3;800 in advance of the towers. My on-screen terrain guidance moved from yellow to blue. I believe I was clear of the towers in altitude as shown by my on-screen indicators; but should have been at the proper altitude earlier. The switch in the flight and change in destination; I checked the charts and did not get the right mef [maximum elevation figure in a quadrant] on the VFR charts. It was discovered by visual indication on my terrain guidance as well as on the call from approach.

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Original NASA ASRS Text

Title: The pilot of a Beechcraft BE35 flying at 3;100 feet was warned of obstacles ahead on his flight path by ATC. He also received warning of the impending catastrophic conflict with the towers ahead by his onboard terrain guidance equipment.

Narrative: On an IFR flight plan from ZZZ to ZZZ1. My original destination was to be ZZZ2; but I chose ZZZ1 due to weather. While in flight I monitored the weather radar to see if it would have been possible to get through to ZZZ2. Radar results were looking positive and I also heard VFR traffic requesting flight following [in a location] which would have been across my desired flight path. I chose to cancel IFR and continue VFR to ZZZ2 with flight following. Visual conditions were clear and I would turn back if I didn't like what I saw. I selected direct to ZZZ2 from my present position which took me directly over four towers referenced above. [Approach] asked confirmation that I had the towers in my view; which I did. At the time; I was at 3;100 feet which would not have been sufficient. My on-screen terrain guidance showed red and I increased altitude to 3;800 in advance of the towers. My on-screen terrain guidance moved from yellow to blue. I believe I was clear of the towers in altitude as shown by my on-screen indicators; but should have been at the proper altitude earlier. The switch in the flight and change in destination; I checked the charts and did not get the right MEF [Maximum Elevation Figure in a quadrant] on the VFR charts. It was discovered by visual indication on my terrain guidance as well as on the call from Approach.

Data retrieved from NASA's ASRS site as of July 2013 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.