414 Power Settings and Configuration for IFR

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  • #84211

    Hey Everybody,

    I’m currently flying a 1974 C-414 (straight model) with a RAM VI conversion. My question is, what power settings and configurations do you guys prefer to use for precision and non/precision approaches? We went through this during SimCom training, but I would like to hear the opinions from others with experience in this airplane.

    Thanks
    Garrett

    #98798

    Hi Garett,

    This other thread is centered around the 421C, but I suspect the MP settings are very similar. https://www.twincessna.org/forum/viewtopic.php?f=5&t=1179.

    How many hours in the 414? Where are you flying? What numbers did Simcom provide for takeoff, cruise, etc.

    Eric

    #98802

    Thanks Eric

    This is close to what I was looking for.

    I have about 80 hours in the C-414 now. Great flying airplane, much better performance than what I was used to (upgraded from a V-tail Bonanza). It’s a California coast runner, but there is a few occasional trips east (Reno, Vegas etc.) I’m very comfortable in the airplane now, but I am still consistently fine tuning things.

    The numbers we used in the sim are pretty close to the numbers discussed in the forum you posted. They essentially told me to use the RAM numbers for all phases of flight, which I do. My primary area of concern was approach settings. In the sim (421C sim) we used 22″ gear down and flaps approach at the FAF fix. This seemed to provide a stabilized descent for any style of approach and kept the airplane at about 120kts. The first few VFR fights in 414 I used the same numbers and the airplane felt way too fast (130-135kts after FAF). At the end of the day it ended up being 16-18″, gear down, flaps approach to hold 120kts comfortably so that’s what I have been using. For fun I tried putting flaps down to 30 degrees at the FAF and 23″ MP during VFR practice approaches. This was quite stable and held the airplane at 115-120 kts comfortably, but I don’t think its the safest practice (engine failure, go-around, level off on a non-precision approach etc). Anyways, that’s why I was curious to see what everybody else was doing.

    Being in Northern California I am consistently shooting approaches down to minimums (AM coastal fog) and I have heard different people use different techniques. It can be a quick transition from IMC to visual when you break out at DH and have an average size runway.

    #98804

    That’s great! One of the reasons the 421C numbers might be different is the prop is huge,and at low MP settings the drag is considerable. Your numbers seem reasonable.

    Another 421C oddity related to the geared engine is leaving the prop at cruise setting vs all the way forward. This is to avoid chattering the gear box. Do you go full forward on the prop?

    Full flaps at FAF is not generally a good practice as full flaps + gear and an engine failure = not enough climb performance. I am sure you would clean it up just fine, but one less then to worry about is good too!

    #98805

    When I had my 414, I found 17-18″ to be the norm going down an ILS. 22″ is way to high. A 421 uses totally different numbers.

    #98806

    Ok good to know I’m in the ballpark. I usually don’t go full forward on the props until short final. On initial descent I typically leave them were they were in cruise. Usually near the FAF I’ll bump them up towards 2500RPM, but no higher. 2500RPM usually allows the prop levers to be about 3/4 full. Situation permitting Ill bump the remainder up before landing in preparation for a go around. My understanding is that the geared engines are a completely different animal.

    #98807

    [quote=”SGERBER”]When I had my 414, I found 17-18″ to be the norm going down an ILS. 22″ is way to high./quote]

    What RPM was that at and how were you configure

    Andrew

    #98816
    quote avann:

    quote SGERBER:

    When I had my 414, I found 17-18″ to be the norm going down an ILS. 22″ is way to high./quote]

    What RPM was that at and how were you configure

    Andrew

    2300. I’m doing this from memory but this is how I flew my 414. I always did cruise power descents. I never touch the mixtures unless I had to go around or miss. These big Continentals don’t like going full rich unless you’re pushing the power forward. For an ILS, during the last 5-7 minutes before intercepting the localizer I start slowing up. I’m usually around 22-24″ 2300 when I receive the 30′ vector towards the intercept. That should put you near gear speed. Depending how far out you are from the FAF 22 2300 and clean will keep you at a good speed. Once you are about to start down the GS you will want to slow up to blue line +10kts. I put in my 15′ of flaps just before going down the GS bring the power back to 18 2300 that should bring you just above blue line. I drop the gear and that should bring you down the GS just above blue line. For non precision step down approaches I always keep the power up for the legs that require being level. I never want to have to jamb the power forward for the leveling legs. Use the last level to do your final slow up for the final descent.

    #98817

    Sandy,

    Nice details. I am just about to start getting initial 414 training and this is exactly what I needed.

    Glenn

    #98818
    quote SGERBER:

    quote avann:

    quote SGERBER:

    When I had my 414, I found 17-18″ to be the norm going down an ILS. 22″ is way to high./quote]

    What RPM was that at and how were you configure

    Andrew

    2300. I’m doing this from memory but this is how I flew my 414. I always did cruise power descents. I never touch the mixtures unless I had to go around or miss. These big Continentals don’t like going full rich unless you’re pushing the power forward. For an ILS, during the last 5-7 minutes before intercepting the localizer I start slowing up. I’m usually around 22-24″ 2300 when I receive the 30′ vector towards the intercept. That should put you near gear speed. Depending how far out you are from the FAF 22 2300 and clean will keep you at a good speed. Once you are about to start down the GS you will want to slow up to blue line +10kts. I put in my 15′ of flaps just before going down the GS bring the power back to 18 2300 that should bring you just above blue line. I drop the gear and that should bring you down the GS just above blue line. For non precision step down approaches I always keep the power up for the legs that require being level. I never want to have to jamb the power forward for the leveling legs. Use the last level to do your final slow up for the final descent.

    Thanks, similar to what I do in the 340 although find 22/22 with flap 15 and gear down keeps me stable and a good speed.

    Now since I’m in the market for a 421, give me the drum on that!

    Thanks

    #102495
    sthibault1
    Participant

      Looks like the last post was eight months ago but this is a great topic. I have been training pilots in Twin Cessnas, mainly the pressurized models, for the past twenty years and every pilot is excited to learn the power settings for their airplane.

      My goal has always been to be at 120 kts at least three miles prior to the FAF, and to maintain this speed until I see the runway or go missed. 120 kts is the minimum speed I will use while in the clouds.

      The first set of numbers I begin with is 20″ mp and 2300 rpms (1800 rpm for the C-421). In a clean configuration this will probably give you 120 kts. This works for 90% of the airplanes I have trained in. Occasionally it might be 20″ +1 to -2″ mp to get 120 kts.

      When I join the glideslope I lower the gear and 15 degrees of flaps. I will not change the mp/rpm setting. This should give you 120 kts while flying down the glideslope. If my speed creeps up I might have to reduce the power by an inch or two to maintain 120kts. The C-421 normally requires 19″ mp while on the glideslope in order to maintain 120 kts.

      Keep in mind, this works while flying the glideslope at 120 kts ground speed. In the back of the government approach book or in the approach book supplement when using ForeFlight, you will find a CLIMB/DESCENT TABLE. Look at this if you have not recently. It shows that a 3 degree glideslope flown at a ground speed of 120 kts requires a descent rate of 650 FPM (637 FPM). If you have a 15 kt headwind (105 kt ground speed) you will have to descend at 550 FPM while on the so it will require a slightly higher power setting – about 1- 2″ mp. A tailwind will require a slightly lower power setting.

      Don’t forget to add power if you have to level off for a circle-to-land. It will require a power setting somewhere between 26″ and 29″ mp, depending on your airplane, in order to maintain 120 kts. Don’t let your speed drop below 120 kts until you are ready to descend below the circling altitude. That said, about 90% of the pilots I train fail to increase power when leveling off. This can be dangerous and you will lose about 1kt/second. This has been the cause off many accidents in many types of airplanes over the years.

      Take your plane up and try this out in your favorite practice area then try it on a few approaches. Use these power settings for every approach. It sure makes flying the approaches easy and predictable.

      Safe flying,
      Steve Thibault

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