Approach climb limited weights (2.1%)

Landing Climb limited weights (3.2%)

 

Approach climb

 

- approach flaps

- Gear up

- 1 Engine inop

 

Landing Climb

 

- Landing flaps

- Gear Down

- Thrust > 8 sec

 

Anyone explain why for the approach climb it assumes 1 engine inop and for the landing all engines working?

Probably because you don't land at flaps 30 or 40 on a single engine.

Right i figured that out.

 

Something else thats got me thinking.

 

Approach climb is 2.1%

Landing climb is 3.2%

 

I'm looking in my FCOM PD: landing climb limit weight,

 

Is that referring to the approach climb of 2.1% ????

 

Now look at - ENGINE INOP: Go-Around Climb Gradient flaps 15,

 

Is that referring to the landing climb of 3.2% or is it for the missed approach climb gradient or MACG >2.5% for OEI flaps 15.

Probably because you don't land at flaps 30 or 40 on a single engine.

 

Is it also giving an example of both cases?

Without seeing the exact chart you're looking at, I can't comment on what the limit is specifically. The weight will be the most restrictive of the following: Approach Climb, Landing Climb, Enroute Climb, or structural. Here's an example.

The As are Approach, Es are Enroute, and O is overweight. 

Without seeing the exact chart you're looking at, I can't comment on what the limit is specifically. The weight will be the most restrictive of the following: Approach Climb, Landing Climb, Enroute Climb, or structural. Here's an example.

 

Its in the 737 FCOM PD JAA operators. And that still won't tell my answer

Approach Climb 2.1% and Landing Climb Limit 3.2% both are limiting weights for the final LCLW or landing climb limit weight. My question is in my FCOM PD: Landing climb Limit Weight what decides what i'm using?

Usually with weight limits you use the most restrictive one, as was said earlier.

Usually with weight limits you use the most restrictive one, as was said earlier.

 

What has enroute weight got to do with LCLW

What has enroute weight got to do with LCLW

You didn't mention enroute weight in the post before mine, nor in your OP.

The start of my post only talks about the approach phase

 

 

What has enroute weight got to do with LCLW

Enroute Climb limit weight can be more restrictive than the other weights, and thus become the climb limited landing weight. Just so we're clear, enroute climb, as per 14 CFR 25.123 is:

 

Climbing at V_FTO with:

The most unfavorable center of gravity;

The critical engines inoperative;

The remaining engines at the available maximum continuous power or thrust; and

The means for controlling the engine-cooling air supply in the position that provides adequate cooling in the hot-day condition.

 

Resultant climb gradient must be no less than 1.1% for twin engine airplanes.

 

As to your question, if it doesn't plainly tell you on the chart, there's no way to know. This makes sense, since for dispatch you normally don't care what's creating the limit, only what it is for planning purposes. If you are landing at LAX on the 24s/25s, the only obstacles in your flight path are several thousand miles away across the Pacific, but you still have to comply with the climb-limited landing weights. That's what the airplane is certified to do, and an operator is not going to exceed it. 

Enroute Climb limit weight can be more restrictive than the other weights, and thus become the climb limited landing weight. Just so we're clear, enroute climb, as per 14 CFR 25.123 is:

 

Climbing at VFTO with:

The most unfavorable center of gravity;

The critical engines inoperative;

The remaining engines at the available maximum continuous power or thrust; and

The means for controlling the engine-cooling air supply in the position that provides adequate cooling in the hot-day condition.

 

Resultant climb gradient must be no less than 1.1% for twin engine airplanes.

 

Thats nothing to do with class A performance aircrafts. Or does it relate to CS 25 large aeroplanes and EASA land.

 

the only obstacles in your flight path are several thousand miles away across the Pacific, but you still have to comply with the climb-limited landing weights. That's what the airplane is certified to do, and an operator is not going to exceed it.

 

Of course and only take into account the 2.1% which is a certification req as per EASA CS-25 and operationally we should comply with EU-OPS and PANS OPS doc 8168 which prescribes 2.5% as procedure design gradient unless otherwise noted. eg Salzburg requires a MACG greater than the NET 2.5%

Approach climb limited weights (2.1%)

Landing Climb limited weights (3.2%)

 

Approach climb

 

- approach flaps

- Gear up

- 1 Engine inop

 

Landing Climb

 

- Landing flaps

- Gear Down

- Thrust > 8 sec

 

Anyone explain why for the approach climb it assumes 1 engine inop and for the landing all engines working?

Actually this will depend on the aircraft's certification. The jets I flew or fly now are FAA cert'd and it was called missed approach climb gradient requirements. In these jets, the data was all engine in the go around configuration. In my mind, you know your climb capability engine out based on your performance planing so no need to re-calculate it if your are shooting the approach at or below that weight. The performance manuals had charts specific to all engine missed approach.

 

I would recommend you search through the 737 performance manual, which should give you information on which the charts are based on. Usually the manuals go into detail with explanation. I'll read through my BBJ performance manual, though i govern them, not fly them. I'll report back.

Actually this will depend on the aircraft's certification.

 

Good old EASA

 

Certification Specifications for

Large Aeroplanes

CS-25

Of course and only take into account the 2.1% which is a certification req as per EASA CS-25 and operationally we should comply with EU-OPS and PANS OPS doc 8168 which prescribes 2.5% as procedure design gradient unless otherwise noted. eg Salzburg requires a MACG greater than the NET 2.5%

This is incorrect. Per CS-25.123, there is an enroute EO climb requirement. CS-25.123 says

 

For the en-route configuration, the flight paths prescribed in sub-paragraphs (d and © of this paragraph must be determined at each weight, altitude, and ambient temperature, within the operating limits established for the aeroplane.

 

 

Therefore, your climb-limited landing weight, while only speced to include Landing Climb and Approach Climb (CS-25.119/121), can be limited by Enroute-Climb, because the airplane needs to be able to meet enroute climb to be within it's operating limits. As shown in the chart I posted, this can be the limiting factor for performance if certain factors are met.

 

And for the record, this almost exactly the same working as 14 CFR Part 25, which you would have noticed if you bothered to take even a cursory glace at it.