holzmann From United States of America, joined Jan 2011, 374 posts, RR: 0 Posted (3 years 3 months 2 weeks 1 day ago) and read 2689 times:
Last Monday, I departed SLC for BWI in a DL 757. I fly several dozen times per year, domestically and internationally, in a variety of aircraft but the DL captain did something on Monday that I haven't experienced in many years. He stopped and held for take off permission at the base of the runway. He then set brakes, put the spurs to her, waited for a good 5-10 seconds it seemed, and then released brakes, and we rocketed off into the mountains. This "set-brake-power-release" phenomenon doesn't happen to me very often but it makes for a more exciting take off. Is there any particular reason why the captain may have opted to do this in SLC or was it just his takeoff style of sorts?
AA737-823 From United States of America, joined Mar 2000, 6091 posts, RR: 12
Reply 1, posted (3 years 3 months 2 weeks 1 day ago) and read 2636 times:
If weather conditions are right for fan blade icing, then the pilot will sometimes spool up and check instruments for excessive vibration before he begins his roll. If there are vibrations present, as on a recent CO flight I took out of ANC on a 737-900, you will hear the engines spool up and down, in an effort to sling the ice off of the blades.
If you listen to ATC at a wintry airport, you'll often hear the heavies request thirty seconds for engine run up.
Not saying that this is what was going on for your flight, but it's a likely scenario.
I've also seen pilots do this in the dead of a hot, dry summer... for which (as a mechanic) I have no explanation.
KC135TopBoom From United States of America, joined Jan 2005, 12259 posts, RR: 51
Reply 2, posted (3 years 3 months 2 weeks 1 day ago) and read 2611 times:
While that is unusual, it is not a prohibited manuver. He may have selected that type of take-off performance due to weather conditions, such as a high field pressure atlitude and he needed the extra performance for obstical clearance, or get altitude seperation for traffic near the departure end of the runway. The B-757 is the hot-rod of commerical airliners, and has no problem doing a manuver like this. But, clearly, I am just guessing as I was not there.
rivervisual From United States of America, joined Jan 2009, 51 posts, RR: 0
Reply 3, posted (3 years 3 months 2 weeks 23 hours ago) and read 2469 times:
could also be due to higher than normal wind speeds or mountain wave related issues. SLC sits in a valley at the base of the mountains so if there was potential for windshear or mtn wave related airpseed fluctuations then a takeoff like you describe may be warranted.