captain_jeeves the performance calculation is always based on the worst case scenario namely engine out at Vef its a requirement from the law maker JAR or FAA doesn't matter.
When is single engine go around usually a problem? Well, if you come for the approach shortly after take off with one engine inop, correct? Because the aircraft is above max landing weight. Therefore you have to make sure that the go around performance is met. Here is some extraction from our manual:
The published missed approach is the preferable procedure to fly in the event of missed approach. The following paragraphs define a procedure to allow the pilot decide whether the constraints of the published missed approach are met in the single engine scenario. The standard published missed approach is based on a climb gradient of 2.5% to a specified final altitude. It does not include a level off segment for acceleration and clean up. TOGA thrust is available for 10 minutes, and the aircraft must level off and clean up within these 10 minutes).
The following table presents the maximum altitude that can be reached during a single engine missed approach at maximum landing mass. It accounts for maintaining at least 2.5% climb gradient to a level-off altitude; acceleration and configuration clean up within the 10-minute TOGA limitation at that altitude.
To follow the published missed approach, the following criteria must be met:
• Below maximum structural landing mass (187,000kg)
• Missed Approach Final altitude or MSA is lower than the maximum altitude specified in the following table.
• Published missed approach does not have a climb gradient greater than 2.5%
• There are no positional constraints. I.e. must reach altitude X by position Y.
The EOSID must be used whenever:
• Any one of the above criteria is not met.
• Whenever the commander has doubt about the aircraft's climb performance. • In Kathmandu. When following the published missed approach, the engine out acceleration altitude is the level-off altitude or MSA, which ever is lower.
there's a table giving you max level off alt which will allow you to determine the max alt you can reach and maintain in case of single engine. Your go around level off alt must obviously be below.
Cheers.