A320 RTO bellow 72kt: Spoilers question.

[lfbb]

Please correct if I am wrong…
On the A320 in case of a RTO is initiated bellow 72kt with the spoilers armed, the ground spoilers will only be deployed if at least one reverser is select. Is that correct?
If no reversers is selected there will be no spoiler deployed if the RTO is initiated bellow 72kt… is this correct?
Thanks!

[LA931]

That is actually a good question. The FCOM doesn't say anything about ground spoiler extension below 72 knots.

You said they will extend when you apply reverse on one engine, but according to the FCOM that happens when the spoilers are not armed and speed exceeds 72 knots.

I guess they will not extend below 72 knots, just like autobrake will not work below that speed.

[mnttech]

I know they don't in our simulator, found something in the FCOM about it. I'll try and look it up tonight. Bottom line IIRC it's the SEC that does it, and you have to be over XX knots.

[VRSCSE2]

If the take-off is rejected prior to 72kts, the spoilers will not deploy and the auto-brake will not function.

VRSC :ok:

[FlightDirector7]

Hello lfbb,

To answer your question as to whether spoilers will extend at speeds below 72kts during an RTO, the answer is NO. The ground spoilers only extend in the case of an RTO when 3 conditions are met :

1. Spoliers are armed
2. Aircraft ground speed is above 72 kts.
3. Thrust levers are brought back to idle.

If the spoilers were not armed for the take off, then in case of an RTO they extend only when the thrust levers are brought to reverse. To add more food for thought, auto brake MAX is not available below 72 kts as there is no spoiler extension. For MAX auto brake to activate, spoilers have to extend and aircraft speed has to be more than 40 kts.

Hope this helps.
Cheers

[matthewgamm]

If the spoilers were not armed for the take off, then in case of an RTO they extend only when the thrust levers are brought to reverse Interesting! Is this regardless of a/c ground speed, i.e. < 72 knots ?

[SIDSTAR]

Below 72 kts no spoilers and no Autobrake regardless of any other conditions. They simply won't deploy.

Worse still, on the A320 there is no manual extension, believe it or not. Pulling the SB lever will do nothing.

Next time in the sim ask the TRE to give you an engine failure below 72 kts on a wet runway with the crosswind from the wrong side - very interesting situation. Nosewheel tiller is your last line of defence!

The spoiler and Autobrake "logic" has been implicated (at least) in a number of accidents/incidents.

[NVpilot]

The spoiler and Autobrake "logic" has been implicated (at least) in a number of accidents/incidentsPlease elaborate, and do you think that spoilers are required below 72 KTS?

[PK-KAR]

The need for a speedbrake/ground spoiler below 72kts?

Next time in the sim ask the TRE to give you an engine failure below 72 kts on a wet runway with the crosswind from the wrong side - very interesting situation. Nosewheel tiller is your last line of defence!
You still got manual braking and the antiskid... I don't see how it would be less or more interesting that if you still got autobrake down at that speed. Btw, try it on a 737 too and see if you get autobrakes...

Spoiler and autobrake logic has been implicated in a number of accidents/incidents? On the 320?

Boeing autoground spoiler on RTO only works up to 60kts... and the autobrakes are active above 60kts but won't initiate unless you initiate reject with wheelspin of 90kts or more...

So, I don't see the major difference here in the "logic" on an RTO... except that you can't manually deploy the ground spoilers... then again, do you need ground spoilers for an RTO at <73 knots?

PK-KAR