Yesterday I was a passenger on board a 737-600 for a late evening 45 min flight. Approx 50 pax on board and a 3900 m. Rwy, winds calm, +5C. I was amazed at the low (derated) lake-off thrust selected and the very poor initial rate of climb. About one minute into the flight, a significant increase of thrust was felt. The noise outside must have been significantly reduced!
Is there a defined derated thrust limit, or is it up to the pilots to decide the minimum thrust required based on runway length, weights etc.?
The landing took place without reverse thrust (wheel breaks only), and I have experienced that only once before. How common is that?