my take-off minima for private operations with my Seneca II:
200 ft ceiling and 400 m visibility on a runway at least 4000 ft / 1,200 m long, 100 ft wide, ILS, flat terrain around, near MSL, 20 ° C, at 2,000 kg / 4,400 lbs. Things change a lot with terrain, density altitude and mass.
Clean-up (gear, flaps, vyse) as soon as possible;
if an engine fails when cleaned up and the runway is very long - lets say 8,000 ft, even being at 300 ft in the clouds I'd always close the throttles, gear down again, flaps when runway in sight, and land. At low visibility ILS is always set to HSI 1 initially.
I've simulated single engine go-arounds and stuff like that at a safe altitude (4,000 ft above the ground, one engine shut down completely). If the aircraft is well maintained, the second engine will bring you to the next airport safely. I recorded climb rates at 250 kg below MTOM, 6,000 ft DA, that were identical to a Cessna 150 at MTOM at the same altitude. So it's not a glider. At this altitude, 65 % on one engine gave me 94 KIAS (vyse + 5 kts) at 10.5 GPH. A lot of endurance available (I had 110 GAL in the tanks) to think over all options and not even challenging to fly for a properly trained pilot.
When being in hard IFR, over water, at night or during the winter time, I just want to have that second power plant, like said before. Even on a PT6, the prop or its governor could fail. What is true: too many twin accidents occur because of wrong emergency procedures, leck of trouble-shooting and the wrong choice after an engine failure close to ground. Better close the throttles and overshoot the runway in the unlikely event of an engine failure short after lift-off.
Emergency landing in a turbine powered causes much higher speeds and thus risks compared to C172, although the event is rather unlikely. But one day production failures might affect even a PT6, and if it is only due to a supplied part, the fuel system or the prop.
With both engines running, a twin offers a much steeper angle of climb than most singles, which adds safety.
A sudden total engine failure is not the normal case. In many cases, power on the affected engine can be reduced before things get worse (e.g. loss of oil) or partial power is still available (loss of one magneto). I've experienced both of this. The oil leak in C303; at least I could see the oil running out of the engine, because the engine wasn't in front of me; reduced power to idle, landed uneventful 30 min later, still 3 qts in the engine which survived (the leak was easy to fix).
To reduce the risk of an engine failure due to high engine load and especially right after departure, I maintain below max. MP during take-off on long runways (e.g. 38" instead of 40") and reduce to 75 % at 300 ft AGL.
I regularly do fly without the aid of the autopilot in solid IMC, practice crosswind landings, approaches in low IMC and emergency procedures. The redundancy of all the instruments and power sources (gyro air, electrics) is another important benefit. However, the pilot must be able to cross-check all these redundant instruments during an approach to minimums. Adequate cross-checking (altimeters, both LOC + GS) is trained rarely, unfortunately. Many instructors and examiners even don't want to put both HSIs / NAVs on the ILS, but the second one already for the missed approach.
These are just my thoughts about flying safely in marginal weather.
Best regards,
Andi
Last edited by AndiKunzi; 6th Oct 2012 at 21:35.