Instrument speeds help

[jhk770]

Passed the Instrument written and just finished equipping my plane for IFR. Starting IFR flight training soon. Trying to get a head start on my own by nailing down the SPEEDS. Could someone help me with the speeds they use to get me in the ballpark. (I have a RV7A with an IO-360 w/ fixed prop) Thanks.

[bkervaski]

Congrats! I'm about to take my written .. any notes? Using the King's School IFR course for study material (sorry for the thread drift).

[Mark H]

There are lots of threads on this subject if you search for ?approach speeds?. I have been working on my instrument rating and like to fly the approach at 90 KIAS. In my plane it?s easy to transition to landing configuration from there, but I have a Hartzell and you might find it a little harder to slow down with the fixed pitch prop in order to get to full flaps. I don?t put the flaps down until landing is assured. Just my opinion though.

[scrollF4]

I may get flamed for this, but I find myself flying power settings rather than speeds. This with my prop at about 2500 rpm. SkyView gives me a power percentage readout as I adjust manifold pressure.

IFR maneuvering, vectors, and on approach outside the FAF: 70-75% power.
Approaching FAF preparing to descend: 60% power
Last 500-700 of glideslope approaching DH/MAP: 30% power or less
Runway in sight: Power back as required to configure.
TRIM TRIM TRIM

Nothing scientific, it just works well for me. YMMV

[h&jeuropa]

Mark,

There is a new video on Pilotworkshop.com that explains what speeds you need to know and how to derive them. It?s in the Missing Lessons series.

I use an old textbook from Pilot Instrument Courses by Peter Dogan that explains them well.

Good luck on the Instrument Rating. You?ll learn a lot.

Jim Butcher

[lr172]

Your instructor may want speeds in the 100 MPH range, so discuss with him first. In my training, I used 100-110 on the approach. You can practice a bit while VFR to figure out the RPMs. You'll want a target RPM to go to once setting up the approach. After the initial setup, you'll adjust the RPM a bit to keep your airspeed on the desired target or range.

Some will argue that the RV's are easier to keep on the GS at higher speeds and I would concur. However, I felt it was a better learning experience to do the approaches at the slower 100 MPH speed. It is more work to maintain the GS, but you are in training and should be striving for mastering the most challenging scenarios. It also takes out the drama of slowing down for landing. Your instructor is going to leave you under the hood until 200 AGL on most every approach and you don't want to then figure out how you're going to lose 50 mph and add flaps when 1 mile from the runway. Especially early in your training. Once you're more experienced, you will learn to slow down gradually down the GS or at certain AGL steps/points. But that is not something you want to add on to the pile during your early learning.

With an FP prop and low ceilings, you're going to spend some amount of time on the GS at 100 MPH, so might as well learn how to do it.

I got my rating in my 6 and really enjoyed it. I am sure you will as well.

Larry

[BobTurner]

I personally like airspeeds around 90 knots (or top of white arc, if lower) and usually one notch of flaps for practice approaches, and that works well for beginning students. But keep in mind that in the real world, you’ll want to be able to go faster or slower, too. I’ve had ATC ask for best possible forward speed when mixing with jets; and I use 75 kias and flaps 20 for approaches into 1/2 mile visibilty at night, aiming to get configured and stabilized prior to 1000’ agl.
PS Living in flat NJ can lead to some bad climb habits. Out here in the west, departures call for Vy climbs until you are assured of terrain clearance. There are a surprisingly large number of western airports with a higher-than-standard climb gradient requirement. In extreme cases you may need Vx. Although, usually not a problem in any RV.

[jhk770]

Thanks so much for the great advice and encouragement. I?m really looking forward to the training.