IFR training in your RV

[recapen]

Like a number of others, I am working on getting my IFR rating in my RV. In my case it is a 6A with IO360B1F6/MT 3 Blade CS prop, 430W, SL70, SL30, and S-Tec-30. Round guages on the pilot side except for the HSI replacement GRT-Mini-AP.

A bunch of hood time has made me better all around from a procedures perspective.

Hardest part for me is maintaining airspeed and altitude simultaneously. What are you been-there-done-that types using for your approach airspeed and how do you maintain it?

MAP, RPM, and mixture are things that I am trying to standardize on and my instructor is pushing me to checklist these items. We're currently using full rich, 2500RPM, and about 16"MAP as part of the stabilized approach technique.

Suggestions and best practices appreciated!

[Auburntsts]

Here's a thread that you might find relevant with respect to speeds and configuration. It was originally an RV-10 discussion but other RV models chimed in with their settings: http://www.vansairforce.com/communit...d.php?t=145951

My own limited experience faster tends to be more stable, but as a student slowing down gives you more time to think so my vote is shoot for 90KIAS but I did my IR in a 172 so take that advice with a grain of salt.

[lr172]

Originally Posted by recapen

Hardest part for me is maintaining airspeed and altitude simultaneously. What are you been-there-done-that types using for your approach airspeed and how do you maintain it?

Maintaining altitude while level or while on approach?

On non-precision approaches, I was flying them around 120 MPH and just matched RPM to the airspeed I wanted. I didn't tightly track A/S on non-precision approaches and my instructor didn't seem to mind. When I was ready to decend, I used 1300 RPM (O-320 w/FP) and would bleed speed down to 100 MPH before decending after the FAF. I would watch A/S more closely on the final decent to MDA.

If you meant precision approaches, I did everything off of Vertical speed, not altitude. I found 1300 RPM usually gave me 500-600 FPM and 100 MPH, but it varied a good bit based upon the wind. A fellow VAF'er recently suggested using MP instead of RPM for stabillizing approach speeds. I will be playing with this method on my next practice session. Trim for 100 and use throttle to stay on the GS.

In cruise, the best method for altitude control is trim and the 6 has a very tight resolution for electric trim adjustment. I control trim via the stick and also have a panel mounted trim switch. On the panel mount swtich, I wired in a home-made voltage reducer and turned it down to around 9 volts. This cuts the trim speed by about half and it is much easier to quickly set a trim position.

With that said, I have to watch ALT and VS like a hawk. The 6 just doesn't like to stay at the same altitude for very long on it's own unless perfectly trimmed in still air.

I just passed my IFR check ride a few weeks ago.

Larry

[BobTurner]

Originally Posted by lr172

I didn't tightly track A/S on non-precision approaches and my instructor didn't seem to mind.
Larry

Doesn't anyone do timed approaches anymore? They won't work out well - and you might even become a statistic - if you don't know and control your speed.

Ideally, get the plane stabilized at level and desired airspeed before the FAF. Then, in principle, you can stay on GS (or level if non-precision) with just the throttle. Let the trim do the work and airspeed will hardly change. The practical problem is that it's hard to make really fine throttle adjustments. So for small GS deviations use pitch (and immediately re-trim) and accept small airspeed changes. It takes some practice to figure out what a small deviation is, and when you do need a power adjustment.

[nigelspeedy]

G'day Ralph,

Glad you are enjoying the instrument training/practice.

I am a slave to 2 things when flying IFR: Power + Attitude = Performance and Trim or Die.

I think it is time well spent to figure out what power you need (MAP, RPM & Mixture) at various conditions i.e. straight and level at a desired airspeed or a ROD at a desired airspeed. Putting them in a dedicated approach checklist is a good idea. If I set these values the aircraft can't help itself but give me what I want. At least it will get me close and then I can make small changes from the datum to take into account the conditions of the day.

Trim. This buys you time to do other things like read an approach plate, tune a radio or program a GPS. If you dont trim the aircraft is not going to be where you left it when you finally get back to it. You will just go from one UA recovery to the next which is pretty stressful.

Cheers

Nigel

[RV6-KPTW]

Ralph,

I did my IFR training and checkride in my RV6. It is a handfull compared to more common commercial aircraft. A Pitch / Power / Performance table for your specific aircraft is very helpful. Trim was mentioned in a post - agreed.

I found 90 knots to be my best approach speed. Slowing to short final for flaps with my airplane is relatively easy - your results may vary.

Dennis

[Auburntsts]

Originally Posted by BobTurner

Doesn't anyone do timed approaches anymore? They won't work out well - and you might even become a statistic - if you don't know and control your speed.

By that I'm assuming you mean using time to determine the missed approach point and not a no kidding "timed approach" from a fix where there has to be an operating tower. I've never done the latter but I did the former on a VOR-A just the other day. The issue is with the proliferation of GPS approaches it seems you have to almost go out of your way to use an approach that has time as method to determine the MAP. That by no means invalidates your point on speed control which is another component to a stabilized approach.

[Larryskydives]

On RPM and MP. In single engine, I get stabilized before getting to the FAF. Typically, I would suggest trying 2200RPM and 15/16 MP. You want to have your speed down to where you can get 10 degrees flaps out. I don't push the prop in until I reach the DH or have the runway insight. Each aircraft is different, you have to find what works best.

[waterboy2110]

I assume at some point you'll fly to min either under the hood or actual. You'll need to get the plane set up for landing. My instructor helped me with this tip and I use it even in VFR.
Providing the approach is stabilized, at 1000 AGL I chop the power and give three swipes to the pitch trim nose up (Cessna). This slows me down and keeps me centered on the needles. Once in the white I can deploy the flaps and start looking for the airport.
If you wait to long it's going to be a fast rollout or missed. If you don't find and master a technique for transition you will loose the needles.
For the comments on timed approaches - I recently read an article promoting at least to make note of the time in case the GPS went south so you would at least know when to generally go missed or look for the airport. Made sense and I will start making note of the times as part of the approach briefing.

[BobTurner]

Originally Posted by Auburntsts

By that I'm assuming you mean using time to determine the missed approach point and not a no kidding "timed approach" from a fix where there has to be an operating tower. I've never done the latter but I did the former on a VOR-A just the other day. The issue is with the proliferation of GPS approaches it seems you have to almost go out of your way to use an approach that has time as method to determine the MAP. That by no means invalidates your point on speed control which is another component to a stabilized approach.

Yes, I meant using time to determine the MAP. I apologize to all for mis-using FAA terminology (I see it's already propagating in other posts). But, I guess it could apply to real (FAA definition) timed approaches. They won't like it if you lose separation minimums because you went faster or slower than expected.