JackG

We generally don’t do static takeoffs. Under certain wind conditions, it can be a problem for the engines to sit still at high power. As the post explains, we sometimes do it to shed ice from the fan blades. In other conditions, I might run up the engines as I’m holding on the runway & anticipating takeoff clearance, but only to about 40%. The usual procedure is to release the brakes, run up the engines to 40% (which will start rolling the jet forward), check that they made it to 40% & that all indications are good (fuel flow, exhaust gas temperature – better known as EGT – oil pressure, vibration) then push the throttles forward. Once they are standing up at about the 12 o’clock position, engage the autothrottles & let them push the throttles the rest of the way forward. When they get to your thrust setting, the pilot flying calls “check thrust”. The pilot monitoring checks the engines again & verifies that the thrust is at or above the setting calculated & replies “thrust set” if all is good. Sometimes the autothrottles slip a little & don’t make it all the way to your calculated setting; if so, the pilot monitoring just moves them up manually. The post also explains that we almost never use all the thrust the engines can produce…we aren’t jamming the throttles all the way forward. Instead, we calculate a “de-rated” or “reduced thrust” setting for the conditions & runway. This saves wear & tear on the engines & airlines often get a discount on maintenance for doing so. It might sound counterintuitive, but I also like to think it’s safer, as running an engine as hard as it will go could damage it & that’s not a good time to damage an engine. We always have the option to push the throttles all the way forward, though, if something doesn’t look right. In addition, there are some scenarios we won’t use a reduced thrust setting, such as very gusty winds or the possibility of windshear. We want all the power to punch through any sudden loss of airspeed. On some short runways, the pilots might elect to do a static takeoff, but it’s not required. On reaching a certain altitude, the thrust setting will automatically change again & the autothrottles will adjust. It’s usually a thrust reduction to help noise abatement, but it can be an increase in some situations. Oh, and I’m aware I’ve used the word “throttles” here, but they are more correctly referred to as “thrust levers” now. I don’t really know why, sorry, but that was new to me when I got to the airline world…the military called them throttles.