I was spotting at Elmendorf when I came across this fellow.
I followed using Traffic Toolbox and this C17 was nose up and down the whole time. Gear and flaps are down too.
Any hints on what is happening here?
KJ

Here's an update.
I thought we were on final since the altitude was dropping at a steady rate.
But finally the gear came up, airspeed climbed and held a steady 154kias and we started gaining altitude.
The porpoising finally stopped but the aircraft then developed a wing waggle from side to side. This eventually stopped as we gained altitude.
At FL100 the aircraft is almost stable. But the flaps are still fully deployed.
Climbing thru FL300, airspeed is dropping and flaps are still deployed.

At FL460 the airspeed was 104kias and the porposing started once more.