LLRX

this video is a must-watch if you’re following the Florida Learjet crash: A meteorologist and pilot wanted to know how is it that a plane equipped with Doppler radar did not see the storm ahead? Turns out that the onboard radar can tilt and if the pilots had tilted it downwards, they would have seen that stronger storm building up. How did they figure this out? They took the actual National Weather Service Doppler radar data from the storm, then recalibrated and resampled it to simulate exactly what a Learjet’s onboard Collins WXR-840 X-band radar (the 3 cm wavelength system many of these jets carry) would have seen at 35,000 feet in −47 °C air. The result is striking. At a normal 0° tilt, the returns look like faint ice-phase echoes. A nothingburger, basically. Tilt the same radar down roughly 5° and it suddenly lights up with the stronger lower core of a rapidly intensifying storm directly ahead. NWS data shows the storm tops were around 31,000 ft just before the jet penetrated, shot up to 40,000 ft while they were in it, then collapsed back to ~33,000 ft after they exited. This confirms that they flew into a storm cloud with explosive growth and collapse with violent updrafts and downdrafts, exactly the kind of thing an X-band radar looking straight ahead at cruise altitude can easily under-sample. @EricBurrisWX walks through the radar geometry, the crystal reflectivity at those temperatures, and low-key gives one of the clearest, most technically grounded explanations out there.