On August 17, 2018 Perlan 2 made it's second tow into the stratosphere. We awoke to pounding rain from 4:30-5 am followed by snow flurries. But after that frontal passage the skies cleared as Dan Gudgel had forecast. Linda took the photo of the day at sunrise. On this flight (only #48) Jim and Miguel Iturmendi towed behind Arne in the Egrett to just over 44,000 feet (Flight Level 440). We did not expect wave. But each pilot needs to be experienced with the challenges of stratospheric flight. This is the highest documented tow ever of a glider and it was another "rocket ride." They were at 40,000 feet in 45 minutes from takeoff. So almost 1,000 feet per minute on average behind the powerful Egrett. Jim said:
Today the team flew Flight 0048…the forecast was not as good as the previous days said it would be, so we did an exploration to confirm what the forecast said…we towed to FL440 (a new unofficial highest ever glider tow)…if you look at the plot below, the Egrett which is flat rated to FL280 had constant climb rate to that level. Above the climb rate gradually tapered off as expected…did some test points on the way down…logged 3.0 hours.
Behind those test pilot words is a satisfying story for aviation enthusiasts around the world. Perlan Project is a full up experimental program. We have a great team who have repeatedly demonstrated that we overcome challenges safely with inventive solutions. After high tow #1 (flight #47) we improved several items. For instance the main wheel tire was serviced with nitrogen; this time it was still round upon landing. ATA said our flutter data showed no anomalies. However they asked for a more extensive frequency range as we are going higher. Morgan programmed that in between high tow #1 and #2. The new tail camera heater circuit worked for the entire flight.
Mike made a clear vision plenum for both the left and right eyeball windows. These worked well on tow, but the "balmy" -50 C (-58 F) was more than they could keep frost free for the entire 3 hour flight. For those who have flown the Perlan 2 simulator - imagine the eyeball visibility being reduced in size to just the pupils of those eyes. See the photos for a real idea. Jim removed the plenums to scrape the frost off before landing........We continue making other improvements and re-calibrations.
If you want to stay connected to our endeavors we have a new text service which will notify you each time we launch. Then you can connect to Perlan's Virtual Cockpit to have altitude, airspeed, moving map, and Twitter feed coming directly from CapComm (Capsule Communication) in El Calafate. In the US text "Perlan" to 57682. Or you can share your email with us on the front page of our website to get an email when we are about to fly. Or you can follow us on Twitter to get all the latest info.
And for a real treat, below is a link to our YouTube video of the Perlan 2 releasing on high tow #1 at 40,000 feet. The tail camera footage clearly shows the glider above the contrail of the Egrett. At about 40 seconds is the release with gentle pull up and turn. For other glider pilots: Jim did not want a full circle due to the strong winds blowing him out of a weak lift band. He did not want a high speed notch at 40,000 feet due to true airspeeds. So a zig zag turn indicates release from tow. The curvature of planet Earth is starting to be visible on the clear day from flight #47. On the higher tow #48 there was a white undercast with white contrail, white glider and white tow plane. Not the best for a video ;>)
Perlan Soars! Jackie