Why can't wing-mounted spoilers be used to steepen approaches?
1
$begingroup$
In a comment on this answer to my previous question about tail-mounted airbrakes (lack of), @JohnK states: You won't see flight spoilers (speed brakes) being used to steepen approaches. You have to be 10kt above Vref to extend them on a CRJ900 and you shouldn't be that hot in the first place, and you aren't allowed to use them at all below 300 ft. Why do you have to be going abnormally fast to slow down with the spoilers, and why can't they be used at low altitude (especially given that, just like with airbrakes, it would seem to me like spoiler extension would be a safer method of slowing down than pulling the throttle all the way back would be, since, should a go-around become necessary, the spoilers can retract a lot more quickly than the engines can spool up from idle to ...