flyingcheesehead
Touchdown! Greaser!
Pulled from another thread... I'd like to continue with this scenario:
As an alternative, I had suggested this possibility:
To which Ron responded:
Using the assumptions in my original scenario, you lose the engine at 600 AGL, one mile from the airport as you enter the clouds (and there's also only one mile vis.)
If you're in the situation where you try to keep flying and potentially smack the side of the mountain... Well, what would you do? You can't climb enough to get back to a published portion of the approach as high as you should.
If you keep flying the ODP, you have two more miles to where you're below the required climb gradient.
If you turn around, right away, you're below circling minimums.
If you turn around at the point where you've climbed to circling minimums, you're outside the protected airspace for circling.
So, what do you do? (I know the right answer is "don't get into this situation in the first place" but that's too easy of an answer, and won't lead to much discussion. )
Here's the only approach to that airport: http://204.108.4.16/d-tpp/0712/00457I27.PDF
TAKE-OFF MINIMUMS: Rwy 9, 600-1 required or std.
with a min. climb of 255' per NM to 1600. (The other runways are all more restrictive.)
DEPARTURE PROCEDURE: Rwy 9, climb straight
ahead to 2500 via PIX NDB or IPT LOC Front Course
before proceeding on course.
You're going on a cross country flight with some friends, loaded to gross with people and fuel. Conditions at IPT are 00000KT OVC006 and 1SM. You take off, and at 600 AGL/1100 MSL you enter the clag, just as you have an engine fail. You already noted, of course, that the takeoff mins and obstacle departure procedure state that you should climb via the ILS localizer front course or PIX NDB to 2500 feet and that you need to maintain a minimum climb gradient of 255'/nm to 1600 feet.
IIRC, the Seminole's Vyse is 88 knots. I don't have the charts handy for performance data at the moment, but you'd probably be lucky to get 100fpm out of the Seminole - Single-engine service ceiling is only 3800 feet, which means the best you could possibly do is 50fpm at 3800, so 100fpm shouldn't be too out of line. At 1.5nm/min, that means your climb gradient after the failure is 67'/nm. Assuming you got to 600' (AGL, 1100' MSL) in one mile with both engines, a fairly reasonable assumption, that puts you below the climb gradient after 2.83 nautical miles, at about 1250 MSL. So far, that's only a loss of the terrain separation required by TERPS, but there's rocks below causing that. The best you can do is to stay on the localizer at Vyse.
It won't be enough. By my calculations, the aircraft wreckage will be found at approximately 2200 MSL on the side of North Mountain.
As an alternative, I had suggested this possibility:
At that point, 1nm from the airport and 600 AGL there's a potentially better option - You're almost up to circling minimums, so you could make a left turn (note the "circling south of runway 9-27 NA" on the plate), probably a 210-degree teardrop, and then let down until you can see the field (hopefully).
To which Ron responded:
If I've already entered the clag when I lose one engine in a twin at 600 AGL, I am most unlikely to try a turnback unless I'm on fire. I will already have Vyse and a good bit more by that point, and even if I'm above the circling mins, I'm almost certainly well outside the protected zone for circling (see Figure 5-4-23 in AIM Section 5-4-20f) so I have no idea what altitude to which I can safely descend. Therefore, if the airplane is still flying and there's no reason to believe any more problems are imminent, I'll fly the SIAP.
Using the assumptions in my original scenario, you lose the engine at 600 AGL, one mile from the airport as you enter the clouds (and there's also only one mile vis.)
If you're in the situation where you try to keep flying and potentially smack the side of the mountain... Well, what would you do? You can't climb enough to get back to a published portion of the approach as high as you should.
If you keep flying the ODP, you have two more miles to where you're below the required climb gradient.
If you turn around, right away, you're below circling minimums.
If you turn around at the point where you've climbed to circling minimums, you're outside the protected airspace for circling.
So, what do you do? (I know the right answer is "don't get into this situation in the first place" but that's too easy of an answer, and won't lead to much discussion. )
Here's the only approach to that airport: http://204.108.4.16/d-tpp/0712/00457I27.PDF
TAKE-OFF MINIMUMS: Rwy 9, 600-1 required or std.
with a min. climb of 255' per NM to 1600. (The other runways are all more restrictive.)
DEPARTURE PROCEDURE: Rwy 9, climb straight
ahead to 2500 via PIX NDB or IPT LOC Front Course
before proceeding on course.