Moderators: richierich, ua900, PanAm_DC10, hOMSaR
Starlionblue wrote:The three probes you're referring to, labeled "5" in the pic, are Side Slip Angle (SSA) probes. They're vanes (similar to AoA vanes), not tubes. Avionics upgrades rendered them unnecessary, so newer builds don't have them. They're being progressively removed from older tails.
MrHMSH wrote:Starlionblue wrote:The three probes you're referring to, labeled "5" in the pic, are Side Slip Angle (SSA) probes. They're vanes (similar to AoA vanes), not tubes. Avionics upgrades rendered them unnecessary, so newer builds don't have them. They're being progressively removed from older tails.
Thanks for your answer. I guess I should have known they weren't pitot tubes, but couldn't link a picture and didn't know how else to describe them! Do you think that most of the older builds will have them removed, or is it not worth the effort for some of them.
Horstroad wrote:Why were the SSA probes needed in the first place? I don't think any other aircraft have these probes (except for the A380).
Is it used for gust suppression similarly to the gust suppression pressure transducers near the leading edge of the vertical stabilizer of the B777?
They seemed to be pretty important to airbus as they put three of them on the aircraft.
What replaces them? Differences in Air Data between the LH and RH side of the aircraft or IR Data or a combination of both?
Also why are there so many probes in general? Correct me if I'm wrong but I think the probes labeled '2' do AOA, pitot and static all in one. There's already triple redundancy (I assume one each for captain, FO, and an independent backup), so why is there one extra set of each? AOA (7), pitot (6) and static (3).
Also the placement of the static port seems odd as they are somewhat front-facing. Won't they also collect some ram air? Or is there a boundary layer or parallel airflow "shielding" the static ports from the ram air at this point?