Re: airbrake question

"Ron Parsons" <[EMAIL PROTECTED]> wrote in message
news:[EMAIL PROTECTED]
> In article <[EMAIL PROTECTED]>,
>  [EMAIL PROTECTED] (WaltBJ) wrote:
>
> >However, some, like the 727, say
> >'no speed brake use with flaps extended' since loss of lift because of
> >turbulence behind the s/b results in aero center shifting aft
> >resulting in a marked nose-down reaction and loss of altitude. Not
> >good on approach.
>
> Actually that is because a loss of hydraulics with both s/b and flaps
> out leaves the s/b floating, still causing drag whereas if they were
> down, they would stay down for the most part.
>
> There is very little pitch change with 727 speedbrakes even if you only
> deploy one set, ie the inboards only, or the outboards. So little that
> you can't use them to offset unwanted pitch like you can on a 707 or 135.

Which are, like any airliner, completely different from a fighter speed
brake.