NASA (which does a lot of atmospheric testing unrelated to space flight) has completed an independent test of the V-22 and tiltrotor technology. While some had thought the NASA test would call for abandoning the V-22, the study instead found no reason to stop development and deployment of the Osprey. Indeed, the NASA panel called for expanding the test program with more aircraft in order to fully understand the "vortex ring state" phenomenon that caused a previous crash. The NASA study called for better rate-of-descent information to be provided for pilots and for changes in the restrictions on rate-of-descent in various conditions. They want a warning indicator added to notify the pilots of any violation of these restrictions. They want more training on how to avoid and recover from vortex ring state problems by programming simulators to cover them. NASA also wants testing done on formation flying to see if the air disturbance caused by multiple aircraft generates unrealized problems. The NASA study recommended dropping requirements that the aircraft be able to land in all engine-failure conditions without killing the passengers or crew since no helicopter can meet such standards.--Stephen V Cole