Living With Nexrad

I finally got around to catching up on back issues, and came across "Soft Spot" (Editors Log, January 2009), having spent June through September flying from Alaska to and around the lower 48. I relied heavily on my Garmin 496. On August 24, 2008, I had a short leg from Springfield, Mo., to Marion County, Ark. Nexrad showed a line of cells marching across the middle of my flight path. Between the weather briefing and the animated radar, I knew these were moving to the southwest, and I knew the speed of their movement. Space between the cells looked pretty good, so I anticipated I could find a decent path through. Given the technologys delays in displaying radar data on the 496, I chose a path just on the back (upwind) side of one of the displayed cells. I figured it would have moved on from my path and I could get through the gap before the next one arrived. This worked exactly as expected, putting me essentially in the clear area between the two. This meant my flight path headed southeast, instead of almost directly south, from Springfield. The diversion added very little to the flight time, but made the VFR flight very comfortable.

Key Takeaways:

• A pilot effectively used a Garmin 496's Nexrad weather display to navigate around storms, highlighting the importance of understanding the technology's data delays and limitations for safe tactical decisions.
• The article corrects a previous statement on impact physics, clarifying that kinetic energy is proportional to the square of velocity, but impact force calculations are more complex due to varying stopping distances during a crash.
• A pilot seeks clarification on Decision Altitude (DA(H)) for LPV and LNAV/VNAV approaches, questioning whether descent below DA(H) is permissible during a missed approach, and noting conflicting expert advice on the matter.

Key takeaways sponsored by Aviator Pro | Start Your Training ->

See a mistake? Contact us.