T/O 2nd segment vs. APP clb

[Sidestick_n_Rudder]

That got me thinking when reading on fuel dumping. Current rules require fuel jettison system to be installed on an a/c if it is not able to meet app/ldg climb requirements during turn back 15 minutes after t/o.

Now, since the a/c is fulfilling all the takeoff performance requirements at MTOW (including 2nd segment), under what circumstances the app/ldg clb criteria would be more penalizing?

2nd segment is 2.4% at MTOW
App clb is 2.1% at MTOW-15mins of fuel

I know there are differences between those two:

2nd segment is at TOGA, possibly optimum flap config and optimized V2
App Clb is at thrust level 8s after accept from idle, g/a flap setting and speed close to Vref

Would that account for a major difference?

[what_goes_up]

If you have a specifically designed Engine Out Procedure for the TO calculation. That means you are not able to meet the gradient requirement on straight out departure and, potentially, the required climb gradient (which can be higher than the 2.1%) on the designed Missed Approach.
One could argue, that you then fly the EO SID for a Missed Approach, which could be your out of jail card.
Other problem could be that the departure Runway hasn't got the required Approach Aid for the Landing and the Landing Runway has a higher Missed Approach Climb Gradient requirement.

[MarkerInbound]

Boeing in their Aero magazine in 2007 said if you meet all the requirements to take off from a runway you meet all the requirements to land on it. The approach climb and landing climb limits come into play when you are landing on a different runway than you departed on.

[what_goes_up]

@Marker
This is, according my understanding, certainly true for the brake performance and, most likely, for "standard" 2.1% (2 ENG) App Climb requirement. However, this might not be true if you depart VHHH and have a 7.1% requirement for the approach. That is, why you would have an Engine Out SID for a TO from this runway.
On the B777 there is an MEL for inop Fuel Jettison where you have to calculate the Missed Approach Gradient at your TO weight minus 2'450kgs for a quick return.

BTW the link for said article is here:http://www.boeing.com/commercial/aeromagazine/articles/qtr_3_07/article_03_1.html

[MarkerInbound]

We have engine out procedures for the 7s in VHHH in order to meet the obstacle clearance requirements. It's separate from meeting 2nd stage climb. Both of them go NE about 6 miles and turn to a 185 heading through the Ma Wan channel, almost an overlay of the Logan 3 departures. If I lost an engine leaving VHHH and had to shoot the ILS 07L to come back I would tell ATC we are unable the published missed approach and if we miss we'll go to Rover and then turn heading 185. The same thing that made us legal to depart in the first place. If they don't like that they can give us 07R.

[what_goes_up]

Agree Marker. That is what I meant with:
One could argue, that you then fly the EO SID for a Missed Approach, which could be your out of jail card.
That is what aviators would do in case of an emergency. However, the regulator says you have to meet the Missed Approach Gradient for the published procedure.

[Lantirn]

How the regulator says this? The regulator doesnt account single engine ops, PANS OPS are crystal clear about this, they talk about regulations during normal ops.

Single engine ops are operators responsibility.