The Sentinel is small stealthy pilotless aircraft. It probably has has one small T34 jet engine and no weapons. The US uses them all over the mideast to spy on other countries. They replace the famous U2 piloted by Gary Powers as he spied over Russia during the Cold War.
Last week - our government claims - that we were using a Sentinel to spy over Afghanistan - when it went out of control. Iran claims they shot it down - yet the trophy they are showing has no damage. At any rate - they have it - and we lost one.
The Air Force is claiming the TQ-170 is not our best technology. It is simply a small jet platform equipped to carry cameras and other spy equipment. I can't imagine our country ever flying over Iran on purpose. :-)
It reminds me of the German ME163 Komet.
The Komet was a small rocket powered aircraft the Nazis used to shoot down B-17 bombers over Germany. It launched off a small trolley left behind during takeoff. It was able to fly over 600 MPH - way faster than anything in the 1940s. It had one cannon carrying about 40 rounds - and it only carried about 8 minutes of fuel. After it did its damaged - it powerlessly glided back to the base landing on a center skid. It was quite an aircraft for being flown 70 years ago.