The emergency descent altitude is almost always 10,000 feet. This is because most people will be able to breath without the oxygen mask at this altitude. But, do not take off your mask.
They do not descend lower because, succinctly, what if all engine power is lost? If that happens then the pilots want enough altitude to have enough time to try and restart the engines and, failing engine restart, to extend gliding range in effort to maximize choices of where to land.
Qualifications: expired VFR license (not a commercial pilot)
And to add to the conversation(if there’s anything incorrect please let me know) from videos I’ve seen by MentourPilot, Captain Joe and online sources
The process will most likely look like the following (assuming an emergency descent is needed because the cabin can’t be pressurized like with the window vs some smaller hole air leak):
They will put on their own o2 masks (it’s critical to do this as you can lose consciousness in under a minute)
They will set the transponder to a code that denotes the emergency to both ATC and nearby traffic
They will radio the distress both for ATC but also nearby planes to give them a heads up that they’ll be rapidly descending. If it’s in a high traffic area they may wait for approval to begin descent (and you can be sure ATC is going to be moving planes out of the way.). If it’s taking too long they will begin descending anyway.
They’ll announce to the cabin that they’re doing an emergency descent
They will start a rapid descent to 10,000 ft (if terrain allows it, otherwise down to whatever they can safely get to). This is because the emergency o2 is limited to about 15 minutes.
Some interesting things I learned about this.
They will often use autopilot for the descent and level flight. This is because of limited visibility and a risk of possible issues caused by low o2.
They turn on all lights to make sure they’re as visible as possible to other traffic.
This descent will be really unpleasant. Not a gentle descent but the safest one (especially if they’re unsure if there’s any structural issues) they can do. Which will be quite a bit steeper than anybody is used to.
So passengers on the plane will experience this as:
Loud rushing noise. Possible moisture filling the cabin now that you have outside cold air mixing with warm air and surfaces inside
Masks dropping and seatbelt signs
Shortly after the Captain saying “Emergency descent” 3 or so times
Flight screw scrambling to seats and putting on masks
The sound of the wings adjusting for speed brakes, shuddering from the flight profile change,
The sounds of the engines being revved up to the planes maximum speed as the nose of the plane tipping down. It will feel like it’s faster than it really is with the shift in gravity followed by being pressed back due to the increase in speed during descent.
The plane shifting as they turn away from the main traffic area as they descend (unless told otherwise by ATC, etc)
Think about “aviate, navigate, communicate” and add to your pilot procedure. For example, the first priority is that the pilot in command establish straight and level flight.
Also, relate that descent to things people know, such as the typical max climb and descent angles passengers experience and the maximum grade found on US interstates.
Your work is pretty good. I encourage you to pick up the textbooks used in flight school. There’s lots of ways to be a pilot without actually obtaining a VFR license, such as a recreational license or MS Flight Simulator. You can even get a taste with a type of skydive called an “assisted free fall”.
Halfway decent comment so adding more:
The emergency descent altitude is almost always 10,000 feet. This is because most people will be able to breath without the oxygen mask at this altitude. But, do not take off your mask.
They do not descend lower because, succinctly, what if all engine power is lost? If that happens then the pilots want enough altitude to have enough time to try and restart the engines and, failing engine restart, to extend gliding range in effort to maximize choices of where to land.
Qualifications: expired VFR license (not a commercial pilot)
And to add to the conversation(if there’s anything incorrect please let me know) from videos I’ve seen by MentourPilot, Captain Joe and online sources
The process will most likely look like the following (assuming an emergency descent is needed because the cabin can’t be pressurized like with the window vs some smaller hole air leak):
They will put on their own o2 masks (it’s critical to do this as you can lose consciousness in under a minute)
They will set the transponder to a code that denotes the emergency to both ATC and nearby traffic
They will radio the distress both for ATC but also nearby planes to give them a heads up that they’ll be rapidly descending. If it’s in a high traffic area they may wait for approval to begin descent (and you can be sure ATC is going to be moving planes out of the way.). If it’s taking too long they will begin descending anyway.
They’ll announce to the cabin that they’re doing an emergency descent
They will start a rapid descent to 10,000 ft (if terrain allows it, otherwise down to whatever they can safely get to). This is because the emergency o2 is limited to about 15 minutes.
Some interesting things I learned about this.
They will often use autopilot for the descent and level flight. This is because of limited visibility and a risk of possible issues caused by low o2.
They turn on all lights to make sure they’re as visible as possible to other traffic.
This descent will be really unpleasant. Not a gentle descent but the safest one (especially if they’re unsure if there’s any structural issues) they can do. Which will be quite a bit steeper than anybody is used to.
So passengers on the plane will experience this as:
Loud rushing noise. Possible moisture filling the cabin now that you have outside cold air mixing with warm air and surfaces inside
Masks dropping and seatbelt signs
Shortly after the Captain saying “Emergency descent” 3 or so times
Flight screw scrambling to seats and putting on masks
The sound of the wings adjusting for speed brakes, shuddering from the flight profile change,
The sounds of the engines being revved up to the planes maximum speed as the nose of the plane tipping down. It will feel like it’s faster than it really is with the shift in gravity followed by being pressed back due to the increase in speed during descent.
The plane shifting as they turn away from the main traffic area as they descend (unless told otherwise by ATC, etc)
Not a fun experience I’m sure
Some sources to check out
Emergency descend!! Cockpit video
Explosive decompression at Simulador TCP. EAS Barcelona pilot school
Pressurisation Problems: Guidance for Flight Crews
Aircraft “Falling” - Emergency descend explained
Expired VFR from above:
Think about “aviate, navigate, communicate” and add to your pilot procedure. For example, the first priority is that the pilot in command establish straight and level flight.
Also, relate that descent to things people know, such as the typical max climb and descent angles passengers experience and the maximum grade found on US interstates.
Your work is pretty good. I encourage you to pick up the textbooks used in flight school. There’s lots of ways to be a pilot without actually obtaining a VFR license, such as a recreational license or MS Flight Simulator. You can even get a taste with a type of skydive called an “assisted free fall”.