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Phase 1 update...N427DK

rightrudder

Well Known Member
I'm almost a third of the way through!

Here's a recap of flights thus far:

1) First flight, 0.7 hours. Cruised around within gliding distance of the airport at 5300', higher than Ontario's airspace ceiling just in case I drifted over. Kept close tabs on CHTs and oil pressure. Slowed down at altitude to 65 KIAS to get a feel for handling in the pattern. Landing was longer than I would have liked!

2) Second flight, 2.4 hours. Everything looked good under the cowling, so buoyed by the success of the first flight, I headed to the practice area...which involves a climb to at least 5500' to follow the Cajon Pass up to SoCal's high desert. Odd to do a bit of mountain flying so early in the process, but once up there it's a big playground. I basically spent the flight at about 2400 rpm learning the visual landmarks on the perimeter of the practice area. Before heading back I did some stalls...Vs was 47 KIAS, and Vso was 39 KIAS.

3) Third flight, 2.8 hours. Calibrated the ASI at three different speeds (80, 100 and 120 KIAS) and used my GPS for heading direction and ground speed. At all speeds, the ASI was reading 2-3 percent lower than actual airspeed. Not too bad, and error in that direction keeps me further away from a stall. Did a couple landings at Apple Valley, and worked on getting the speed down and stabilized in the pattern.

4) Fourth flight, 2.6 hours. Just a joyride to break in the engine, running between 2500 and 2550 rpm. I did this fairly early in the morning to avoid bumpy air in the desert. Mild Santa Ana offshore winds, so coming down the pass got my attention...I went down to maneuvering speed to deal with the turbulence. I made the mistake of descending too early into more turbulent air. Extra altitude next time.

5) Fifth flight, 2.5 hours. More landing practice, engine break-in and some 45-degree banked turns. Ventured up to Barstow-Daggett, then over to Highway 395, the western boundary of my practice area. Practiced leaning technique.

6) Today's flight, 1.9 hours. I cut it short because of bumpy air...not so much in the pass but over the desert floor. This was the first flight with the wheel pants on, and it really gets up to 130 KIAS quick!! During a smoother part of the flight, I wicked it up to about 2750 rpm and saw a TAS of 164 knots (188 mph) and still accelerating (this assumes a 3-percent low ASI reading, consistent with the lower speed calibrations I did). I would've pushed it a little harder, but at this point there was a hint of turbulence so I erred on the side of caution and throttled down. To me, top speed is just a footnote/bragging point; I'm super content just having a 145 KTAS performance cruise.

For the next series of flights, I'll start ballasting the right seat in 80-lb. increments, up to 240 lb. (I've got some big friends!). Also, I need to make a "reset" page for my checklist, for when you land and taxi back for another take-off. Today, I forgot to reset the elevator trim and it felt a little spooky there for a few seconds at rotation.

Looking forward to having the simulated passenger weight and seeing how that affects sink rate on final, stall speeds, etc.
 
Doug, I will be starting my phase 1 flying in mid-March. As part of the learning process can you provide a couple of details. What engine, prop and temp. you were seeing in climb-out and cruse.. Thanks. Mark C.
 
Good job!

I'm fighting high oil temps, got a bigger oil cooler and built a diffuser for the air entering it, I'll get to try that out this Friday and see how much difference it makes. I've got 8.1 hours so far and wheel pants and gear fairings are next on my list after testing the new oil cooler setup.

Once I can keep my temps under control I'll start doing some climb testing.
 
Greg, I hope the new oil cooler and possible revised ducting solve the temp issue. I know it's frustrating to sort this out when you'd rather be flying, but it will pay off in peace of mind and engine longevity.

Mark, I'm running an IO-320-D1A with a Catto 2-blade FP prop, 70x70. I'm getting better cooling now that I cut the air dams in front of cyls 1 & 2 down to about 1/3 their original size.

Yesterday, ambient temp at my field (elevation is about 1440') was approaching 80 F, and initial 1000 fpm climb had CHTs just over 410 F (highest was maybe 415). In cruise climb at 500-600 fpm, they come down to 360-370. At 6500' in the practice area, with 61 F OAT, a 1000-fpm climb has CHTs well under 400 F. It's a big improvement over the 5-hour mark, where the dams were about 2/3 original size. With similar OAT, they were touching 430-435 after takeoff, requiring a more gradual climb to bring them down. I suspect they'll decrease even more as the engine continues to break in. If not, I may trim back the cowl exit by a half inch or so.
 
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A couple of pics from the practice area. First one is east of Apple Valley; second one is coming up the Cajon Pass, where you can see a little snow on a peak near Mt. Baldy. Note that I have the standard "cowl pucker" that you get when using 1/4 turn fasteners. :)



 
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Hi Doug,

Great info. Congratulations again on building one heck of a nice 9. Can't wait to check it out in person on my next trip to SoCal. :D

Take care,
 
Thanks, Vlad and Jim! It's going into the paint shop right after the 40-hour mark... I'll be sure to redo the W&B numbers at that point. We all know it's 10 knots faster with a racy scheme that includes a checkerboard rudder!!! :)
 
Note that I have the standard "cowl pucker" that you get when using 1/4 turn fasteners. :)

Congrats on your progress, I am working to see that view this year!

OK - not the puckers, why? Are they present on the ground, or only flying? i.e. are they only the result of cowl pressure?
 
Congrats on your progress, I am working to see that view this year!

OK - not the puckers, why? Are they present on the ground, or only flying? i.e. are they only the result of cowl pressure?

Exactly...they're from cowl pressure. It looks perfect on the ground. Some go the extra mile and reinforce the cowling where it meets the firewall to reduce/eliminate the pucker, but I'm fine with it. The piano hinge method all but eliminates this, but I didn't want to have to fish the pins out the oil door.

It sounds like you are getting close!!
 
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Exactly...they're from cowl pressure. It looks perfect on the ground. Some go the extra mile and reinforce the cowling where it meets the firewall to reduce/eliminate the pucker, but I'm fine with it. The piano hinge method all but eliminates this, but I didn't want to have to fish the pins out the oil door.

It sounds like you are getting close!!

Do you have a plenum on the engine, or standard baffles to the cowl?
 
Greg, mine has the standard baffles included in the FWF kit.

Bret, I used whatever Skybolt recommended for spacing...I think it's 3 in. The receptacle plates on the upper curved portion of the firewall sorta dictate spacing, although it would be possible to trim them a bit if you wanted them closer together.

I wanted to fly today as there's a storm coming in over the weekend. Winds were quite calm, but there was a haze/mist combo that kept me grounded. Visibility minimums were legal, but the Mk IV eyeball said otherwise. The trip to the hangar wasn't a total waste, as I needed to bring back some tools for around-the-house stuff.
 
This is really exciting, Doug. As I mentioned over PM, your journey has been an inspiration and along with probably many others, I wish I had both the time and the commitment to making progress as efficiently as you have.
Wasn't able to make contact when I was in Laguna last month but am watching your thread intently and if you come up to the Bay, give us a shout out. Plenty of RVs at KCCR I believe!
 
Thanks, Daniel. I'm glad I'm able to provide a spark, just as so many others have done for me. I'll certainly give you a shout if I'm up your way.

Looks like next Tues/Wed after the storm is my next chance to go flying, with a bag of cement riding shotgun. :)
 
It's sunny today after the first storm, but, um, a wee bit breezy in the practice area: 33G43KT out at Barstow/Daggett. A fine day to be on the ground having a cup of hot tea.
 
Before you start modifying anything, back up and think about the big picture.

Your photo looks like SkyBolt fastening system. I also have Skybolt cowl fasteners. I have no puckering. And you are correct, the mounting plates set the fastener spacing.

The region of the upper cowl, near the firewall, should have a low pressure ( relatively), the high pressure zone should be behind the cowl inlets and inside of the engine baffles. That high pressure air escapes down though the cyl fins to mix with the lower pressure air below the engine. All this air escapes at the bottom of the fire wall with the exhaust stacks.

Unless there is a major leakage at the engine baffles seal against the top cowl, then there is a major blockage of the exit air at the bottom exit at the firewall.

I assume this is a standard RV9A cowl system.

I would start with the exit air at the bottom of the cowl at the firewall. All the air that enters the cowl inlets must exit down there. If the exit is choked, then the top of the firewall will have an increased pressure.

The engine cooling depends on the pressure differential between above the engine inside the baffles and the volume outside the baffles as it exits the cowl.
Watch CHTs. Some have had to cut the exhaust forward to increase the exit area.

Good luck!
 
I'm curious as to what others have done. My cowl exit at the bottom is basically flush with the firewall in profile. High CHTs are only a concern if I have a sustained initial climb at 1000-1200 fpm on a hot-ish day, but I figured that this was par for the course with this tightly cowled design.

I'm pretty happy with the baffle seal job I did, but I do think I'd profit from moving the right-side inlet ramp back a little...can't quite make a fist in there, whereas I can on the left side.

whd721, do you have the pink cowling or the old-style white version? The pink cowling is pretty thin where the Skybolts mount.
 
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Right rudder,

I have the old whitish cowls. I will check on my next flight for any pluckers. I have flat black anti-glare at that junction and may not have noticed any slight pucker. However, I added about 2 inches to the rear of the cowl to move the engine forward so I am not typical.

I am now slightly over the 30 hour mark in phase I.

My major issue has been low oil temps. I have flown all the hours with the oil cooler shutter closed. Finally I blocked the oil cooler inlet and got up to 190f.

I also had Aeroleds strobe feedback into the headsets. This was solved by eliminating the wing tip strobe ground at the wing tip as recommended by Aeroleds.

I have also trimmed the front air dams way down.

keep posting guys
 
Hey whd721,

I'm betting the white cowls are thicker near the firewall than the Pepto version, so you're getting no pucker, or minimal amounts.

I flew twice today, each flight a whopping 0.5 on the Hobbs. It was still quite breezy after the storm, so I did an exploratory flight up to the base of the Cajon Pass. I was getting knocked around some from gusts, so being the turbulence wimp that I am, I turned back to the airport. I had 120 lb. of cement in the right seat as ballast, and the extra weight really helps the sink rate on approach. But working at cross purposes was an idle adjustment I made earlier that bumped idle speed to about 800 rpm, from 650. Too much! I put it back down to 650 and while it sputters and gasps at this speed, it continues to run, and as I found out on the next flight, reduces the float over the runway.

I was looking on this flight to find a ballpark power setting to maintain pattern altitude (with full flaps), and what works for me is thus: About 1700 rpm to fly the pattern at about 70-72 knots; pull back to about 1300 rpm abeam the numbers and trim for 65 knots; then back to 1000 rpm trimmed for 60 knots on final, sometimes pulling all the power out/pitching down slightly as needed to get the desired descent. You have to be really patient and set up early with the -9; I found it far easier to hit my aiming spot on the runway in my transition-training -7A that had a more natural-feeling, linear sink rate...but also the sense that the bottom would drop out if you got carelessly low with your airspeed! :eek:

And man, 60 knots seems like slow motion when you've been bipping along at 140 or so!!

My second flight was amazing: I took off just as the sun set, the pattern to myself. Flew east toward San Bernardino, made a crisp 45-degree-bank to double back toward the airport, with runway now lit up. The air was calm, the 210 freeway was ablaze with taillights and the pattern was again empty. It was just dark enough to see my landing light on the pavement. Life is good.

I also met some fellow RV-ers on the field...Joel and his wife Kim, who flew in from their Santa Barbara work assignment to have some graphics applied to their red/white RV-7A by Cable's resident nose art-ist, Victory Girl, aka Jerri (sp?). Super nice folks, all. I hope Joel posts some pics of his -7A with the new graphics. It looks fantastic.

Looks like tomorrow will be calmer, so I hope to add more ballast, fly to the high desert and bore some full-throttle holes in the sky. :D:D:D
 
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Man Doug, please o please keep posting these reports. That made me want to run out to the hangar and get working on my 9A! Thanks so much!

The speeds seem so slow, and do I understand that you fly the downwind with full flaps? I've heard the 9s are hard to slow down. Sure a lot different than my Beech.

Thanks again!
 
Hey Dave,

Yes, keep working! Eventually, a glorious, fully functioning plane will emerge...I'm living proof! :)

At this point, yes, I'm flying the whole pattern with full flaps and keeping the speed down. It just helps to reduce the workload, to get the aircraft stabilized at 70-75 KIAS maybe a mile or so out (and slowed down somewhat at 4-5 miles out). The key thing is to do some stalls at altitude on maybe your second flight to see what YOUR airspeed indicator reads. For me, a power-of stall with flaps extended was 39 KIAS at solo weight, which gave me full confidence to slow it down to 60 on final. Controls do get quite light at 60....and the difference in feel from, say, 80 to 60 is noticeably more pronounced in a -9A than in a Cessna 172 or Piper Cherokee, for instance. So do those stalls and lots of slow flight at altitude early on, and build that confidence.

Maybe later when I have more experience, I can approach the pattern with a little more speed and slow it down mid-pattern, but for now I'm very content to trudge along!

In a 172 or Cherokee, they're draggy enough that when you reduce power approaching the pattern, you're almost automatically in Vfe range, so a quick glance at the ASI and you can start feeding them in. in the -9 or -7, you've just got to be more deliberate, stay ahead of the plane, and go back and forth with power reduction and nose-up trim to bleed off the speed and maintain altitude. No biggie, just a little more planning involved.

One more observation that's old news to RV gurus but new to me: There's so very little adverse yaw with the ailerons that I hardly use the rudder at all when at altitude to keep the ball centered. P-factor on takeoff requires higher rudder control effort than my rental planes, but less throw because of the RV rudder's generous size. I've yet to deal with any significant crosswind, but in coming weeks I'll do some crosswind landings on purpose up in the high desert.
 
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A 2.2-hour flight this morning got me to 16.4 on the Hobbs. The most notable thing was that most of the flight was at 2600 rpm or above for engine break-in. No problem at all with temps on a full throttle sustained climb, from about 2500 ft to 7500 ft, at roughly 600 fpm with a KIAS of about 120. Next time I'll trim for 110 knots and see what that translates to in climb rate (and see what the temps do).

Red cube not calibrated yet, but based on what it took to fill the tanks afterward, fuel consumption worked out to 8.0 gph on this flight. It was hard to discern any oil consumption at all on the dipstick...maybe a cup at most?...so I feel good about the break-in thus far. I'll keep the cylinder pressures up as much as possible for the duration of Phase 1.

Going back and forth across the practice area (8500' westbound, 7500' eastbound), I was working on maintaining a precise altitude with trim and the very slight stick pressure these RVs are famous for. I'm trying for that 5/95 ratio of quickly checking the instruments, then getting eyes outside for the all-important scan for traffic. It's pretty lonely in the high desert at those altitudes, but you never know. Ever mistake a bug splat on the canopy for traffic, just for an instant? [Sheepishly raises hand] I hate that!

It just so happened that Joel and Kim, unbeknownst to me, were at the airport when I made my sunset flight. I noticed some shadowy figures near the taxiway taking pictures, but it was only later that I learned it was them. Thanks for the pic!!

 
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Congrats on working through your Phase 1. I just finished mine and it's great to be able to actually go somewhere.

Not to be a debbie downer, but my Phase 1 limitations said "day VFR only". You may want to check yours to make sure you are in compliance.:)
 
Way to go, Doug. Your control discoveries and observations make me smile .... you perfectly described flying the Nine. :) Until you get used to the slippery airframe, slowing down for the pattern always reminded me of Sky King and "throw out the sandbags, Penny!"
You'll find the Nine is marvelously tolerant of X-winds .... w-a-y more so than any certificated aircraft I've flown. (And especially 172s). Keep up the good work and have a ball!
 
Congrats on working through your Phase 1. I just finished mine and it's great to be able to actually go somewhere.

Not to be a debbie downer, but my Phase 1 limitations said "day VFR only". You may want to check yours to make sure you are in compliance.:)

Yep, "day VFR only" is standard on all op lims for phase I. If not, they were issued improperly.
 
That picture looks like it has a REALLY long taxiway.
And I'm sure there was some after landing checklist items that he did immediately after landing.

That's at least 45 mins to an hour before this picture was taken. Appears to be day VFR to me.
 
It can be very difficult to accurately judge lighting with some many camera variables...
 
Hi guys,

I think I was OK per day VFR as my landing was only about 25 minutes past sunset. It may look a little darker in the picture, but I could've easily landed without the runway lights.

Here's another shot my friends took of me on that flight. I'm right on the horizon, where the base of the mountain and the flatlands intersect.



Rupester, love the Sky Kings reference!! You're so right about crosswinds. So far I've only dealt with an X-wind component of maybe 8 knots and I don't even remember doing anything other than a little aileron input to keep 'er on the centerline. Landings in this thing are an absolute joy... the nose-high flare is very intuitive, and the way it floats at solo weight, you get to enjoy that 5-foot-AGL feeling for a while! I'm getting a lot better at carrying the nose wheel after touchdown of the mains; you have to get it to full back stick pretty quickly. If I'm not fast enough, the nose will do one gentle pogo, but full back will arrest the tendency.

Anthony, yes, I'm dreaming of flying to all possible destinations! But first, to the paint shop....

TFeeney, yes, a long taxiway. Our runway is 3706' excluding thresholds, and I like to roll to near the end to save the brakes a little. Winds usually favor 24, so you're landing downhill, and from the numbers to the VASI, there's an additional downward dip, which adds to the complication (the entire runway is a gentle sine wave in profile). And you fly the pattern in a fisheye cutout of Ontario's Class C, so a bit of a tighter pattern is encouraged so as to not bust airspace, so there's just enough time to level the wings briefly on base before turning final. And I'm essentially doing mountain flying to reach my practice area. And I'd rarely gone to nontowered fields in my previous flying experience. So the learning curve has been steep, but very rewarding! :D

I'm still a little fast over the fence on landings...maybe 65 KIAS, and I need to bring it down to 60. More storms on the way, so the next flight will probably be next Wed. or Thur.
 
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Great story of first flights......

I have been on here for some years and these first flight stories are great cause many of us Cessna drivers are concerned about how the "Sports Car" feel of the (RV 7 mine) RV 9 will be. How will we handle it? What will we experience? Are we capable?

In my case I have checked out in the Citabria and now struggle to afford some aerobatic training while completing my RV 7, but to read your article makes it real and while reading the story it felt like I was downwind and judging airspeed and committing to final for that first landing..... Thanks for that.

I have been learning to fly attitude, feel, and angle of attack rather than gauges while doing aerobatics and hope that will come into play on that moment when you turn final.... the first time... in your pride and Joy!

Again great stories.... sure looked like Day VFR to me... thanks! :D:D
 
I have been on here for some years and these first flight stories are great cause many of us Cessna drivers are concerned about how the "Sports Car" feel of the (RV 7 mine) RV 9 will be. How will we handle it? What will we experience? Are we capable?

All my previous hours were in a 172, go take the transition training from one of the folks offering it, and you'll be fine. The first few hours are exhilarating and very different, and then it will fit like a glove.
 
Hey Dave, Greg's right...the transition training is a must. I did about 5 hours in the RV-7A, and it gave me a ton of confidence for my first flight, despite the -9A's, ahem, greater reluctance to return to earth. :D:D It's the best money you could ever spend. The -7A really liked a touch over 80 knots in the pattern and precisely 80 knots on final (your airspeed may vary of course, depending on the ASI's calibration). At 75 knots it sinks a little more and gets your attention, but at 80 all is right with the world.

You'll find that sweet spot on the first couple of landings in training. Extend the downwind a bit if you can so you have a longish final to really dial it in.
 
Phase I considerations

Phase I Considerations

All Phase I experiences are different and mine is more different than most. I hope this is useful to those who are nearing the start of Phase I.

Overall Summary:

I found the RV9A to be easy to fly but difficult to control.

I found a stabilized approach on base and final to be very difficult to maintain, but the actual landings were fairly easy.
Most of my time is in a Cherokee 140, once slowed down on downwind, drop flaps, set trim, set rpm and it is mostly stable till touchdown. The RV9A is very light on the controls, Look for traffic and the speed will change. Drop the nose a little and the Dynon will yell ?Flaps overspeed?, raise the nose a little and the speed drops quickly. With full attention it is easy to remain stabilized , throw in a distraction and it will wander.

My History Phase I:

-First engine start Dec 2014.

-Transition training Jan 2015.
January, in the Pacific Northwest is the worst time to try and train. Three hours drive each way, rain and fog daily, complicated everything. After eight hours of transition training, the instructor and I agreed I was not ready. The instructor was good, but I was too rusty from trying to finish my RV9A. I spent more than a year thinking I was only a few weeks away from completion.
The final installations and systems checkout surface issues you never noticed before. The saying ? 90% complete and only 90% to go? proves to be true.

-Fortunately, I had decided before the transition training that I would use a test pilot for the my RV9A first flight. I returned from the transition training very discouraged , but still determined to see my plane fly. I contacted my test pilot to start the pre-flight inspection and started the process. During that inspection he remarked that I should check out the new ?Additional Pilot program?.

EVERYONE NEARING THE START OF THEIR PHASE I SHOULD GET A COPY OF THIS PUBLICATION!!

AC No. 90-116 Dated 9/23/2014.
ADDITIONAL PILOT PROGRAM FOR PHASE I FLIGHT TEST.

This program makes sense for new RV pilots. Following this program, I improved my skills and regained confidence in flying an RV.

Then at slightly over 18 hours TT on my RV9A, Connecting Rod #3 failed at 5,000 ft and 2500rpm. Fortunately nothing was bent, but the engine was totally destroyed.

It took till mid August 2015 to receive a new replacement Warranty engine.

October 14, 2015 was the second first flight of my RV9A. The Oregon winter rains promptly started and weather with a 3,000 to 5,000 ft ceiling have been few and far between.

-I am now nearing the end of the 40 hour Phase I ( and still finishing break-in on the second engine).

I am very happy with my RV9A and would recommend it anytime, but it does require a revised skill set.
 
Great observations, whd721.

Wow, a failed con rod at 18 hours. Scary! I'm glad that you were able to set 'er down safely.

What you said about the approach and not overspeeding the flaps was spot on. The -9 just needs that pre-stabilized 60-65 knot approach, which I get with full flaps, up trim and power almost completely out. With 172 and Cherokee spam cans, you've got more power on approach, and more of an option to lower the nose (and/or reduce power) to alter speed/glide slope. Since Vfe is 78 kts on the -9, it doesn't take much nose down to exceed this speed. So I feel like I'm "mushing it in" more than the planes I'm used to, but as long as airspeed stays steady-ish at the 60-65 kt number I'm happy.

It's just a little different way of flying the plane. Make sure you lose a fair amount of altitude on the base leg and reduce power early. Most certainly a good thing to have 3000' of runway in the early going, and be prepared to go around if you're too high.

My experience thus far is the higher your gross weight, the easier it is. My plane is pretty simple and weighs in at 1025 lb. empty, so those with full interiors, three glass panels, CS props, etc. will have an easier time, and of course the CS prop makes a better air brake. A big passenger will be most welcome as ballast! I'm a fairly low-time pilot (about 125 hours pre-RV-9A), so those with more total experience may find it easier too.
 
Doug, do your Op lims allow the additional pilot for Phase 1? Might be easier to find a qualified co-test-pilot than strap in lots of ballast!

BTW, your numbers on landing are identical to what I'm experiencing. Takes forever to slow it down to 78Kts for first notch of flaps (10degs), then second notch on base (20degs) keeping the speed around 65Kts. Last 10 degrees go in on final as I slow it to 60Kts over the numbers. I'm still well in the green on the AOA. I've landed as slow as 57Kts over the numbers, but it really wants to drop in when it is that slow. 60-65 is much nicer and smoother.
 
Doug, do your Op lims allow the additional pilot for Phase 1?
Hmm, I'm not sure Bruce. I probably could've used the additional pilot about 10 Hobbs-hours ago, but I'm feeling pretty comfortable with the way the RV handles. (I guess the trick is to never get too comfortable!)

I'm glad our numbers agree. I learned a lot from you on that flight to El Monte a while back.
 
Halfway there...

The Hobbs clicked over to 21.6 today. Hooray! Getting past the halfway mark is a psychological hurdle I'm glad to have cleared. :)

Great flight today....2.8 hours total. I got up at 0-Dark-Early, drove out to Upland, had a Denny's breakfast and took off maybe 15 minutes before sunrise. The timing worked out perfectly, as I made my turn north up the pass just as the sun peeked over the mountains to the east, so no seared retinas. Verrrrrry smooth air for a change.

The testing du jour was maximum rate climbs at different airspeeds, and here's what I came up with. Timing the climbs for a minute seemed fiddly, so I just stabilized the climb for 15-20 seconds and read the value off the EFIS' VSI. Not super precise, but a good ballpark figure. All climbs started at 5000' MSL, with a full rich mixture and an OAT of about 62 degrees F.

110 KIAS..........900 fpm
100 KIAS..........1200 fpm
90 KIAS............1350 fpm
80 KIAS............1500 fpm

Also here's some numbers at lower elevation and about 67 degrees OAT; a full throttle climb from about 2500' MSL, full rich mixture. The 130 KIAS climb rate was started nearer 2500' and the 120 KIAS climb nearer to 3500'. Again, scrambled data to a degree, but I thought I'd throw it out there.

130 KIAS.........600 fpm
120 KIAS.........1000 fpm

CHTs were great for the most part....just touching 400, but No. 1 goes up to 415 in climb but settles down with the others in cruise. Based on this, I think I need to cut and re-glass the right-side inlet ramp, moving it forward a little to create more space between it and the cylinder. Does this sound right? The air dam is already cut down substantially.

Fuel consumption worked out to 7.2 gph with quite a bit of full throttle for the climb tests, but some taxiing too as I landed at Apple Valley for a bathroom break. For a quick hot restart (say, after 10 minutes for refueling, etc.), I've found that this works great (after a lot of experimentation): No prime, mixture to ICO, throttle to idle, then cracked open a smidge. Crank, and slowly push mixture to full rich. It fires right up.

If it sits for more than a half hour, I go back to the cold start procedure.

Landings felt GREAT today. I'm sure a lot of it was the still air, but another part is a certain inner calm I'm developing as I get more hours in the aircraft. Both were 63-kt stabilized approaches, gentle elevator rides down to the runway. The prior flight I was over controlling the flare, but everything came together today. I'm also getting the hang of slowing the plane down nearer to the pattern, which just comes with practice. Also, I'm letting 'er roll farther down the runway before exiting to save the brakes, as rolling resistance is a lot less than your typical Piper.

Got the synthetic vision working with some help from GRT. An easy menu fix, thankfully! No. 2 CHT sensor needs troubleshooting.




Interstate 15, near the summit of Cajon Pass. Reminds me of a model train layout:




Bathroom stop at Apple Valley. The pink cowl looks especially nasty in this light. Can't wait to get it painted!!!




Descending to get ready for the next climb test. So nice to see some of these rock formations up close. All those trails down there make me want to buy another dual sport bike!




Over Southern California Logistics, with a ton of mothballed airliners....kinda like AMARC. Gotta love that dry desert air!!!

 
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Nice!...did you say 3500 FPM climb? that's impressive! now then, back to sanding my cowl......;-(
 
Nice!...did you say 3500 FPM climb? that's impressive! now then, back to sanding my cowl......;-(
I wish!! But even 1500 fpm seems like a pretty wild elevator ride compared to the stuff I've rented. I couldn't believe how far I was above the desert floor after just a minute or so. :eek:

Sanding sucks....I hope you're done with it soon. The results of a good job make it worthwhile.

Today I determined some cruising speeds at various rpm, done at 6500' MSL. Done without the upper nose gear intersection fairing in place, so it might be a knot faster in full slippery mode:

2500 rpm.........143 KTAS
2600 rpm.........151 KTAS
2700 rpm..........157 KTAS

I think the sweet spot for a decent cruise speed and low noise is right around 2450, where it's doing right around 140 KTAS. My goal on a long trip was to reach a cruising ground speed of 160 mph, about twice what you can (semi-legally) do in a car, and the RV-9A achieves that perfectly.

Only 15.3 gal. burned over 2.8 hours on the Hobbs, so 5.5 gph! This does include some taxiing for a landing at Apple Valley, and from Cable's fuel station back to my hangar. And a leisurely throttled-back float from 8500 ft down the pass to the flatlands.
 
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Getting there.... 27.4 on the Hobbs now. Today's flight was the longest yet at 2.9 hrs.

I redid the right inlet ramp to reduce CHTs for Nos. 1 & 3, shortening it by about 1.5 in. I cut it where it mates to the intake with a Dremel cut-off wheel, sanded down the dry micro with a mini die-grinder sander, then used the remaining shelf to anchor the shortened ramp.

Aft end was secured with a thick bead of flox, then a couple layers of 9 oz. cloth. I sanded down the remnants of the original attachment flush with the die grinder.

The temp variance wasn't all that bad to begin with, but the change seemed to help...all cylinders are now with 10 degrees or so in cruise. But No. 1 still gets the hottest in climb, so I'll have to either remove its air dam altogether, or cut it down by half again.

I'm getting lots of practice with leaning, as I buzz the practice area in one direction, pull a U-eee, richen, climb 1000 ft, lean, buzz the other direction, descend 1000 ft, richen, and so forth.

Did a couple of landings at Apple Valley, and the aircraft is really starting to fit like a glove. After running 'er hard, it's kinda peaceful to throttle way back and just putt-putt around the pattern.

One last thought....it's the little things that make it more fun to work on our planes. A long, skinny funnel I bought from HF slips right down the dipstick tube and stays put. Best $3.99 I've spent lately. :)







 
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Doug,

Did u just cut down the inlet portion of the ramp or did you completely remove it and trim both ends? Wondering if how yours looks now is the way DanH suggests.

Can you get a fist in both sides now? Is that about what you were going for? Any more ideas about how much it may have dropped the temps of 1&3 relative to the others?

I'm considering doing the same to mine.
 
Hey Steve,

I removed it and trimmed both ends. And yes, I can get a fist in both sides, as the spacing from the cylinder heads to the inlet ramps is now approximately equal.

I'd say that the temps of 1 & 3 in cruise have dropped about 10 degrees, so not a huge change but worth doing. I'll pay closer attention on the next flight and write them down on the knee board.

In addition to the higher climb CHT of the No. 1 cylinder, No. 1's EGT is also the highest. I've heard that you can adjust fuel flow to individual cylinders, so maybe if cutting the air dam down doesn't do the trick, I'll seek the services of a professional to richen up No. 1 a little.
 
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Getting there.... 27.4 on the Hobbs now. Today's flight was the longest yet at 2.9 hrs.




. A long, skinny funnel I bought from HF slips right down the dipstick tube and stays put. Best $3.99 I've spent lately. :)





If you are ever stranded faraway and need to pour a quart in, a plastic bottle with bottom cut will work the same way. Good job on flight tests Doug!
 
Thanks for the tip, Vlad (aka McGuyver!) :)

I'm probably waaaaayyy overthinking the CHT issue. Nothing is absurdly out of range, oil temp is totally under control, and I was able to do a glorious full throttle 1200-fpm climb from takeoff (3092' field elevation) to 8500' this morning, with No. 1 getting up to 410 degrees.

Yet, 400 degrees would be better. :D:D
 
Yet, 400 degrees would be better. :D:D

Thanks Doug.

What are your OATs down there this time of year? I've been aiming for getting temps in cruise climb to stay below 400F on days where OATs are 90F or less. Not quite there yet, but gradually getting closer.

If your injected then, yes, you should be able to enrich one cylinder at a time. Dealing with temps as I have I've regretted not having that option with my O320. Oh well, next plane! :cool:
 
Have a look at where your baffling sits on the ramps. On mine, there was a direct path for the plenum air to go under the ramps and squirt out the other side. I closed off the inside of the ramp which now prevents this from happening.
Your baffles may hit the ramp just right and make that seal but it is worth checking.
 
Thanks, JonJay. I think I'm pretty good on the sealing, judging from feeling around in there, and the wear patterns that are starting to emerge from contact.

alp2000, the OATs are varying from about 80-82 F at takeoff from 1440' (yes, we're having a warm spring!) to as low as 45 F at 8500' in the practice area. On the hotter days, I can do a shallow cruise climb (say, 120 KIAS) and have a couple of cylinders just nudge above 400 F.

It'll be telling when summer rolls around to see how that affects temps. When I'm flying around in the LA/Orange County basin after Phase 1, I won't have to push it nearly as hard as I do now, flying up to my practice area. As it stands, it's a continuous climb from my home field to 8500' at the start of every flight, in an attempt to get above the turbulence caused by the mountain pass.

Right now, I'm having more of an issue with EGT variance. I'll post a question over in "engines" to get more eyeballs on it.
 
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Thanks for sharing, what are you seeing on your EGT? I have number 1 just above 1501, and 2,3,4 below 1470. Outside air temp 34 F. MN flying. Do you think you are getting a reduction by cutting the dam back on the lower cowling?
Also, what is your oil temp running at? Thanks.
Jim Fogarty
RV-9A Flying
Dues paid 2016
 
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