Takeoff Minimums

TFaudree_ERAU

Mashin' dem buttons
I've searched long and far for the answer to my question, but have come up empty. I know I should know this, but I'm doubting myself. To make matters worse, I can't seem to put my finger on any reg that gives a definitive answer.

Is the required climb gradient of a non-standard takeoff minimum assuming both engines operative or only a single engine operative (assuming a two engine aircraft)? For safety sake, I would think it is with one inoperative. But then again, how many aircraft can meet the required climb gradient out of places like Aspen assuming one engine craps out at V1?
 
I've searched long and far for the answer to my question, but have come up empty. I know I should know this, but I'm doubting myself. To make matters worse, I can't seem to put my finger on any reg that gives a definitive answer.

Is the required climb gradient of a non-standard takeoff minimum assuming both engines operative or only a single engine operative (assuming a two engine aircraft)? For safety sake, I would think it is with one inoperative. But then again, how many aircraft can meet the required climb gradient out of places like Aspen assuming one engine craps out at V1?

121 world 2 engine ride answer.

The "Four Segment" Climb:

First Sement: Start of T/O roll (point where T/O thrust/power is set) to 35 feet (might be 50, can't find my notes right now...)

Second Segment: Gear up to Acceleration altitude, flown at V2 to V2+10. This requires a 2.4% OEI gradient.

Third Segment: Acceleration to Vfs, Level flight

Fourth Segment : Clean climb at 1.2% to 1500' AGL at Vfs.

Your OEI climb performance (in 121) is normally part of your takeoff performance. That's why ASE is so restricted, and the BACs did so well in there. Second Segment is USUALLY the limiting climb factor out of an airport
 
Is the required climb gradient of a non-standard takeoff minimum assuming both engines operative or only a single engine operative

If you're referring to TERPS mandated climb gradients, they're just telling you the climb gradient you need to clear obstacles by a specified amount. They don't care how many engines you have to achieve it. ;-)

My understanding is that it's the responsibility of the operators to determine engine-out procedures for the airports they use.
 
If you're referring to TERPS mandated climb gradients, they're just telling you the climb gradient you need to clear obstacles by a specified amount. They don't care how many engines you have to achieve it. ;-)

My understanding is that it's the responsibility of the operators to determine engine-out procedures for the airports they use.

True. You might have somewhere like ASE where it's an all-engines departure. If you have custom performance, you will have some sort of engineered escape maneuver, should you lose one on T/O
 
Additional info from Part 25:

§ 25.111 Takeoff path.

(a) The takeoff path extends from a standing start to a point in the takeoff at which the airplane is 1,500 feet above the takeoff surface, or at which the transition from the takeoff to the en route configuration is completed and VFTOis reached, whichever point is higher. In addition—
(1) The takeoff path must be based on the procedures prescribed in §25.101(f);
(2) The airplane must be accelerated on the ground to V EF,at which point the critical engine must be made inoperative and remain inoperative for the rest of the takeoff; and
(3) After reaching V EF,the airplane must be accelerated to V 2.
(b) During the acceleration to speed V 2, the nose gear may be raised off the ground at a speed not less than V R.However, landing gear retraction may not be begun until the airplane is airborne.
(c) During the takeoff path determination in accordance with paragraphs (a) and (b) of this section—
(1) The slope of the airborne part of the takeoff path must be positive at each point;
(2) The airplane must reach V 2before it is 35 feet above the takeoff surface and must continue at a speed as close as practical to, but not less than V 2, until it is 400 feet above the takeoff surface;
(3) At each point along the takeoff path, starting at the point at which the airplane reaches 400 feet above the takeoff surface, the available gradient of climb may not be less than—
(i) 1.2 percent for two-engine airplanes;
(ii) 1.5 percent for three-engine airplanes; and
(iii) 1.7 percent for four-engine airplanes.
(4) The airplane configuration may not be changed, except for gear retraction and automatic propeller feathering, and no change in power or thrust that requires action by the pilot may be made until the airplane is 400 feet above the takeoff surface; and
 
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