Practical vs. Possible

[Ski]

I remember hearing this in the video of the Canadian F-18 trainees but don't understand the difference in regards to importance. While reading our emergency procedures, numerous times I have come across the phrase "as soon as practical". What is the difference between that and "as soon as possible" in regards to importance?

[Energy]

This is just me..
Possible, when you can do that but needs to be done soon.
Practical, do it when you can do it and is convenient to do it.

I know Snoopy, Noodle, Tex and Eddie will correct me or at least make it more clear.

Now that I'm on PC and not on phone:

Hierarchy:
1. Possible
2. Practical

One of your engines crap out.
1. Possible - deal with situation (React via PCL, fly, bring ACFT home)
2. Practical - Manage all the tasks that were not crucial in the previous step (Yaw trim if you will, RTB, plan ejection, do were fitting)

[Eddie]

As soon as possible, esstially means, now and above anything that isn't a higher risk to flight safety. Whereas practical allows for convenience to be considered.

For example an emergency checklist that ends "Land as soon as possible" means you are landing at the closet airport that has a suitable runway without delay. A checklist that ends "As soon as practical" means you need to abort your mission, but you can go to your planned alternate or even return to home plate.

[Noodle]

Edit: Sniped by Eddie because I wrote a novel.

Practical (or practicable, as the FAA likes to say) is synonymous with "feasible". Feasibility depends on external factors such as safety, policy, goals, etc. Possible is synonymous with "able". Ability depends on, well...ability.

Therefore, an instruction like "land as soon as practical" prioritizes operational convenience over urgency, and might mean that you should land at the closest airport that is able to provide appropriate maintenance and/or ground handling services; has a long runway; or has other desirable facilities. For instance, you're in an F-16 with two unexpended inert MK-84s and you have a brake failure. You have a civil airfield with an 8,500ft runway at 10 o'clock and 15 miles, and an Air Force base with a 12,000ft runway and 4 cables at 2 o'clock and 100 miles. You probably want to bypass the "nearest suitable" airport in favor of the more practical one which is etter able to handle your specific emergency (and your aircraft).

On the other hand, an instruction to "land as soon as possible" means that you should land immediately at the nearest suitable airport; do not pass by a suitable airport just because it might be inconvenient. Suitability is determined by things like the nature of your emergency, your ability to control the airplane, your ability to stop the airplane, and that's about it. If the airplane is physically able to safely land on the runway, you should land there. For instance, you're in an F-16 on a low-level route when you notice the engine oil pressure indicates zero. A fat juicy Air Force runway is about 25 miles off the nose, or there's a civilian airport with an 8,500 runway at 3 o'clock and 8 miles. You probably want to get the airplane on the ground as soon as...possible...before the engine seizes.

[Tex]

Eddie and Noodle covered it. Unofficially, the difference is where do you want to drink for the night. For a purely hypothetical example... ... when flying a plane home after a deployment, do you return to the base in Iraq you just took off from (as soon as possible) or continue to Souda Bay, Greece (as soon as practical)? In this case, sleeping another night in a transient tent with no booze just isn't "practical".