Why Do?

CaptainSkidmark

Some pilots semi deploy the spoilers when descending for 3-4 minutes? Now i'm talking still at between 25-35k feet.

I have to admit, IM not the best flier even tho i have a massive love of aviation but it only seems to be Aeroflot pilots i ever see doing it, I travel regularly on Aeroflot B777 and A330 across Russia and i've never seen any other airlines pilots do it before. The aircraft just vibrates like crazy!

Bsal

In the air the spoilers/speedbrake are used to slow down or increase the rate of descent.

...And Justice

I saw the spoilers deployed this way before, when a passenger had a suspected heart attack, the pilot had the aircraft down on the ground within about 15 minutes, in some remote airfield in France. Aircraft was shaking as we descended from cruising altitude at a high rate of decent. Boeing 738.

Negative_G

Spoilers are designed to reduce lift and increase drag. They are typically located inboard of ailerons in the area where the most lift is produced.

Pilots will use them for various reasons. The primary reason is to increase the rate of descent while maintaining a specific speed.

The reasons a pilot may elect to use them vary. They may have been delayed commencing their descent and are now 'above' the descent path. In order to get back on it they may use spoilers to increase the rate of descent until they establish back on a more routine path.

Some aircraft use spoilers in addition to the ailerons to aid in roll control. In other aircraft spoilers can actually function as ailerons in the unlikely event of an aileron jam.

The main thing to remember is that their use is completely normal and they are no cause for alarm.

...And Justice wrote: »

I saw the spoilers deployed this way before, when a passenger had a suspected heart attack, the pilot had the aircraft down on the ground within about 15 minutes, in some remote airfield in France. Aircraft was shaking as we descended from cruising altitude at a high rate of decent. Boeing 738.

You'll find quite often that the the first few items for an emergency descent checklist will contain the following:
1. Thrust levers............Idol
2. Autopilot........Disconnect
3. Spoilers...............Deploy
4. Descend..........VMO/MMO

When time permits, pilots will put out a MAYDAY call and squawk 7700. The shaking in your case was likely caused by the turbulent airflow created by the spoilers.

Growler!!!

Negative_G wrote: »

You'll find quite often that the the first few items for an emergency descent checklist will contain the following:
1. Thrust levers............Idol
2. Autopilot........Disconnect
3. Spoilers...............Deploy
4. Descend..........VMO/MMO

When time permits, pilots will put out a MAYDAY call and squawk 7700. The shaking in your case was likely caused by the turbulent airflow created by the spoilers.

First thing is always oxy masks! Then establish crew comms between each other.

Never heard of disconnecting the autopilot. Just wind the altitude down to begin descent. It is taking care of the flight path for you and reduces workload. In conjunction with the auto throttle (if fitted) it will either keep your current speed if damage suspected or keep you from exceeding Vmo/Mmo if not. Then when there's time fine tune the altitude to 10,000ft or MSA if higher.

Don't forget pax oxy too if the cabin alt didn't exceed 13,500.

...And Justice

Growler!!! wrote: »

First thing is always oxy masks! Then establish crew comms between each other.

Never heard of disconnecting the autopilot. Just wind the altitude down to begin descent. It is taking care of the flight path for you and reduces workload. In conjunction with the auto throttle (if fitted) it will either keep your current speed if damage suspected or keep you from exceeding Vmo/Mmo if not. Then when there's time fine tune the altitude to 10,000ft or MSA if higher.

Don't forget pax oxy too if the cabin alt didn't exceed 13,500.

That's probably why the pilot didn't notify the pax, he probably put on the oxygen mask and got on with the job, he notified us when we were about 7000 feet.

Growler!!!

...And Justice wrote: »

That's probably why the pilot didn't notify the pax, he probably put on the oxygen mask and got on with the job, he notified us when we were about 7000 feet.

A diversion especially a medical division (where time is more critical) is a busy period on the flight deck.
Under communication after aviating and navigating, the passengers are the last on the list to be told anything.

...And Justice

Growler!!! wrote: »

A diversion especially a medical division (where time is more critical) is a busy period on the flight deck.
Under communication after aviating and navigating, the passengers are the last on the list to be told anything.

Great pilot, American guy , we were flying the now dissolved futura airlines. Totally professional.

Steve

I believe it's also when there is a higher than expected tail wind once TOD is reached. From flying PMDG, sims the FMC will warn when spoilers are required to achieve the descent profile.

Negative_G

Growler!!! wrote: »

First thing is always oxy masks! Then establish crew comms between each other.

Never heard of disconnecting the autopilot. Just wind the altitude down to begin descent. It is taking care of the flight path for you and reduces workload. In conjunction with the auto throttle (if fitted) it will either keep your current speed if damage suspected or keep you from exceeding Vmo/Mmo if not. Then when there's time fine tune the altitude to 10,000ft or MSA if higher.

Don't forget pax oxy too if the cabin alt didn't exceed 13,500.

Of course you are correct, masks are the first item.

The type I was familiar with calls for autopilot disconnect. Once initiated, the PM can set the speed bug and baro and you can follow the FD. Once established the autopilot can be engaged to reduce the workload if you so wish.

smurfjed

The B777 FMS VPATH detects that it wont meet the required descent profile, it will call for DRAG REQUIRED using the speedbrakes, once the speed and profile settles down, they will retract the speedbrakes.

deaddonkey15

...And Justice wrote: »

Great pilot, American guy , we were flying the now dissolved futura airlines. Totally professional.

Interesting. I flew with Futura once years ago and remember a distinct American accent from the pilot. I wonder if it was the same guy!

River Song

I believe the 757 FMC will say "DRAG REQUIRED" if it's needed to stay on the descent profile. I've always noticed that the spoilers on that aircraft to be particularly loud, and there's always a little jump of sorts when they're retracted. I always enjoy it anyway!

faceman

Growler!!! wrote:

First thing is always oxy masks! Then establish crew comms between each other.

Is it standard for masks to be deployed during an emergency descent regardless of the emergency?

Steve

faceman wrote: »

Is it standard for masks to be deployed during an emergency descent regardless of the emergency?

In general the pax masks deploy in the event of depressurisation above 14000 feet. The emergency decent is initiated to get back to a breathable pressure altitude.

faceman

Steve wrote: »

In general the pax masks deploy in the event of depressurisation above 14000 feet. The emergency decent is initiated to get back to a breathable pressure altitude.

But in this example procedure quoted earlier the emergency was not depressurisation. Are masks deployed still?

Steve

faceman wrote: »

But in this example procedure quoted earlier the emergency was not depressurisation. Are masks deployed still?

Not sure, pilot masks are at their discretion AFIK, pax masks are automatic.

e.g the case where the BA captain was partially ejected from the cockpit due to a front window failure was above the hypoxia altitude but the co-pilot was able to maintain control and consciousnesses due to the 'ram' effect of the open window.

smurfjed

Is it standard for masks to be deployed during an emergency descent regardless of the emergency?

"(B777) The masks automatically drop from the PSUs if cabin altitude exceeds approximately 13,500 feet. The passenger masks can be manually deployed from the flight deck by pushing the overhead panel PASSENGER OXYGEN switch to
the ON position."

So if the system detects that the cabin altitude is close to 13,500 feet it will automatically drop the passenger masks, or the flight crew can decide to drop them manually.

In the diversion above, i.e. medical emergency, there wouldn't be a need to drop them.

Also remember that most present systems are individual 22 minute chemical generators, so if they are used they would have to be replaced.

Bussywussy

smurfjed wrote: »

"(B777) The masks automatically drop from the PSUs if cabin altitude exceeds approximately 13,500 feet. The passenger masks can be manually deployed from the flight deck by pushing the overhead panel PASSENGER OXYGEN switch to
the ON position."

So if the system detects that the cabin altitude is close to 13,500 feet it will automatically drop the passenger masks, or the flight crew can decide to drop them manually.

In the diversion above, i.e. medical emergency, there wouldn't be a need to drop them.

Also remember that most present systems are individual 22 minute chemical generators, so if they are used they would have to be replaced.

'Mask MAN on' the single worst push-button you can ever press!!!

Growler!!!

faceman wrote: »

Is it standard for masks to be deployed during an emergency descent regardless of the emergency?

I can see I've caused a bit of confusion here. An "Emergency Decent" is usually associated with a cabin depressurisation and the first action of the memory items is for the pilots to don their oxygen masks. This is so they don't succumb to the effects of oxygen deprivation or hypoxia. I was correcting Negative G's comment in regard to the first actions in the emergency descent checklist. The Emergancy descent is a specific manoeuvre. It will not be carried out in the case of a sick passenger.