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Oil Cooler, Day 4

This suuuuucks.   I usually feel a certain smugness when my predictions come true, but not this time.  I knew this was going to blow going in, that’s why I delayed it for so long.  I was on the money with this one.  Not one part of this has gone smoothly.  Most of it has to do with the fact that it’s impossible to suspend an oil cooler in mid-air in the place it will eventually go so measurements for bracketry can be taken.

I guess if it was easy, everyone would do it.  Today I took a different tack, and unfortunately I didn’t take any pictures, because there was nothing to shoot.  Just a lot of head scratching and pondering, followed by some fairly intense metal work.  Oh, and I managed to burn the f**k out of my left thumb and forefinger trying to grab a piece of hot angle off the bandsaw table.

At least I have a proper metal shop to do stuff in, even if it is at the opposite corner of the hangar from where my plane is.

Eventually, I was able to draw up some rudimentary plans plans based on some measurements.  That actually worked and I have a main bracket that should, in theory suspend the oil cooler in the correct position from the engine mount tubes in three places. There is also no chance in hell it’s going to break. It’s reinforced at the cooler mount point with .062 angle.

I also need a new oil hose, which is shaping up to be around $250.  Argh.

Oil Cooler, Day 3.

I thought this was going to be a fairly easy exercise.  After all, what’s the big deal, right?  Attach a flange to the baffle, mount the cooler, fab up some fiberglass ducting, slap on a length of SCEET, and presto, done.

Nah.  Slow your roll, dude.

First thing that needed to happen was removing the old cooler mounting flange.   Rather than take the baffles apart, which may have been a poor decision, I figured I’d just unzip all the rivets along the top and left of frame so the baffle can open up, swinging open from the bend right about where the spark plug wires go in.  That hypothesis was borne out.  After some less-than-stellar de-riveting, I have the baffle exposed, but even opening up, it was difficult to get any kind of squeezer or rivet set into the area by the engine mount tubes.  Before anyone freaks out, yes I did clean up the mangled rivet holes, and a couple of them went away entirely when I cut out some excess for the 4″ flange opening, seen in the next shot.

So now there’s a big plate of aluminum doubling up the baffle, to which is attached a beefy 4″ aluminum duct flange from an industrial dust collection system.  Fun fact about that:  Originally, this duct was two pieces, which included a sliding gate to control the amount of air going through the duct.  Cool setup, but it was not to be.  I either had edge-distance issues or conflicts with other parts of the structure, and it didn’t look like I would be able to set up the control cable and mount it.  Bummer, but that’s the way it goes.   I want to return to flight ASAP, I don’t want to be back to project status for any longer than necessary to make this a safe, effective modification.

The final configuration looks a little different from the above.  The flange is flipped over to provide material to rivet along the top where the baffle parts connect, and I cut one of the tabs off to allow for clearance of something else.   But it looks like I have enough room for a 90 bend of SCEET (or one of those boy-racer intercooler inlet elbows) and a diffuser.

This is where I plan to put the oil cooler.  I’ve checked for clearance to mount tubes, wires, and my fuel line (important, that), and it also clears the lower cowl.  I think I can connect to the engine mount with Adel clamps in at least 4 places, both from above and below.  It also looks like there are no immediate obstacles to exit air, but I’m not sure how airflow will be affected by the proximity of the engine mount tubes, but there is nothing directly up against the fins on the bottom.

So I guess my New Year’s resolution for 2018 is to solve all my cooling issues.  Among the things that keep me awake at night is the possibility that the 4″ duct will now steal too much cooling air from the cylinder heads.  Also on the list is to rework the baffle seals to be fewer, more continuous pieces, made of silicone instead of the black rubber baffle material.

Today is New Year’s Eve.  It’s unlikely I’ll be making more headway on this until after I go back to work, but if I keep it chill on tonight’s festivities, I might be able to put in some work tomorrow.

Happy New Year, everyone!

More oil cooler fun

Finding a spot for the new oil cooler was just part of the adventure.  I needed to make room by disconnecting the plug wires and temperature probes from the left side so I could work.  I also needed to find a new spot for the fuel pressure sensor.  Fortunately, that’s easy. I can clamp it to the top strut of the engine mount, pretty much where you see it resting now, top middle of the frame.

Ordinarily, I hate working with steel.  it’s sharp, unyielding, and awkward to work with.   This all changes when you have the proper tools. EAA 96 has a plump machine shop, with a shear, two sheet metal bending brakes, numerous drill presses, grinding wheels, table saws, a massive lathe, and two Bridgeport mills, one of which is working, but neither of which I know how to use.  There are also a number of projects in the hangar that utilize the tube-and-fabric method, so there’s a scrap can full of 4130 steel tubing and sheet cut-offs.  So that’s where I went to get the brackets I needed.   I’m sure there’s some fancy engineer-y math I could have used to bend a bracket so it works in one piece like papercraft, but I was able to get this together with two pieces.  This connects to an angle brace on the cooler and suspends it from the engine mount at the angle and distance I’ll need to get a fiberglass plenum on it, which will connect to the baffle via 4″ SCEET tube.

I chose steel because it was available, I have the tools to work it, and I can get away with less material.  I don’t have the right circumstances to do a solid aluminum webbing, so steel it is.

There will also be a support member on the bottom of the cooler, where I have to battle the mechanics of attaching to the engine mount without blocking the airflow from the cooler.  I paid for 10 rows of cooling, I want all 10 rows cooling.

New oil hoses will also be a necessity.  The top one barely made it to the cooler with an acceptable bend in the line.  There’s no way it makes it now.   I may be able to repurpose the from-cooler line as the to-cooler line, but that’s doubtful, given the fittings necessary.

Oil Cooling hell.

Yesterday, I went from having a flying airplane back to having a project.  For quite a while now, my oil temperatures on hot days and climbouts have been marginal to unacceptable, and since I have the break in the work schedule, I figured I’d do something about it.   So I joined the Compton EAA chapter and rented a space in the hangar for a month while I sort it out.  My oil cooler is the stock Van’s 7-row Niagara oil cooler that seems to work on most RV installs, but not mine.   There are a few reasons this might be: timing, blow-by (which would suck, the cyls are more or less new) bad baffling (worked when I first flew, so wtf) or carbon deposits in the cooler.  It’s actually fine as long as the OAT is 65f or below.  I can settle in to cruise at 190-195F no problem.  But on hot days, or long climbs, I will go above 220 real fast, and that’s no good.   Last year, I purchased a 10-row cooler with the intention of replacing the stock one, but I never put it on.  I first attempted to seal up any baffle leaks.  This improved things a bit, but not enough to matter.  Cylinder head temps are fine.   I’ll hit 400 on those if I mash it and rabbit up to 10,000ft, but they cool down pretty fast once leveled off, and usually settle in around 350-375.  I’m sure there’s more I can do, but for now I need to solve the big one.

The 10-row cooler will not fit on the back of the baffle like the stock one does.  It’s too wide.  There are a number of ways to mount the cooler on the firewall, but none of them work because my firewall is already full of stuff, namely the RDAC, fuel pump, and brake line fittings.

I supposed I could probably move the RDAC and fuel pump, but that’s less appealing to me than mounting on the engine mount and connecting it with a SCEET tube to a flange on the baffle where the original cooler was mounted.

So it’s off to Compton I go, first to do exploratory surgery, then some design work, and then hopefully some fabrication.  They have ALL the tools.

Painted!

Finally got 313TD painted.  It was time.   The salt-laden dew at SMO was killing the skin, especially underneath the canopy cover.  I hemmed and hawed over various paint scheme ideas, mostly military-themed.   Eventually, that gave way to the practicality of painting it to make it more appealing on resale.  But then I thought, who am I kidding, I’m not selling it, it’s too awesome.  Then on the way to work one day, I saw a BMW M4 Gran Coupe, painted in Singapore Grey Metallic.   I have never before been so captivated by car paint.  The way it captures the ambient light and the prismatic effect of the metallic flakes is fascinating, and the pictures really don’t communicate the full impact of how it works with light and reflection.  One could argue there aren’t enough swoopy lines in the body to make it work right on this structure like it does with a sport sedan’s bone line, hip line, and fender contours, but I disagree.  you really have to see it in person.   In any event, I’m happy with it.   Not only is it protected from the elements, it looks bloody awesome.  The gear fairings and wheel pants still have to be put back on, but since I ordered a set of pre-made RV Bits fairings, I’ll need a facility to install them so I can get the alignment right.   The wheel pants are also gloss black.

Big shout out to Derek Spears and David Prescott, who helped with the movement and various aspects of disassembly/reassembly!

In the hangar, you can see a bit of how this paint is supposed to work.  Right now it’s picking up the greenish hue from the fluorescent lights and the yellow-green skylights, but also the blue bounce from the floor near where the hangar doors are slightly open.

PlanePainted1

Indoors

It’s a dark gray, to be sure, but the way it phases through the blue-green spectrum is awesome, and the black just sets it off.

Here I am, set to head back to Santa Monica with no pants on.

Direct sunlight really does a number on photographing this paint, but it’s still amazing!

Paint!

I dropped off the plane for paint today in Chino at Century Air Paint.  The process involved removing all control surfaces and fairings.   But along the way there was some, uh, stuff, mostly having to do with wires that needed to be cut.

  1. Tail lamp and strobe:   Will need to be reconnected.   Need strobe wire molex and pins.  Or barrels.  Need to look that up.
  2. Elevators: Need new set of DB9 socket barrels for trim tab motor control.
  3. Flaps:  Look at platenut options, because drilling out the pop rivets for the hinge pin retainer fooken sucked.
  4. Need to repair/resolder ground wire on red nav light board
  5. Will need to drill/realign gear fairings to fit new intersection fairings.
  6. Need new MR16 ceramic bulb connector for nav light.
  7. Anti-chafe tape (forgot what it’s called) – for underside of wing skin where flap rides
  8. rubber grommets for strobe/tail light
  9. rubber grommets for trim tab wire

Some tools will be needed for this op:

  1. #40 bits
  2. #30 bits
  3. Flush cutters
  4. AFM8 crimper
  5. multimeter
  6. Red and blue inline wire connectors
  7. Connector crimper
  8. Extra wire
  9. The usual aircraft tool container
  10. Need new MR16 ceramic bulb connector for nav light.
  11. Anti-chafe tape (forgot what it’s called) – for underside of wing skin where flap rides
  12. rubber grommets for strobe/tail light
  13. rubber grommets for trim tab wire
  14. 8R8 platenuts, single sided
  15. Functional #40 size Cogsdill deburring tool
  16. #30 size Cogsdill deburring tool

Hopefully this list will allow me to put back all the things I took off, then fly it home after the paint job.   If you’re wondering about color, it’s going to be BMW Singapore Grey, with black tips and spinner.  Like so:
2013-bmw-m6-gran-coupe-singapore-grey

Full credit for the photo goes to Performance Drive, and you can view the full article here:
http://performancedrive.com.au/2013-bmw-m6-gran-coupe-review-video-2206/

 

Avionics Master Switch

3 hours.

Originally when I built the electrical system, I was of a mind that an avionics master switch is a single point of failure and should be avoided.  I have since changed my mind.  First,  my comm2 radio has no off switch (MGL V6), second, I really want my comm and audio panel volume settings to be set and left alone.   Third, and this is the most important thing, I want to minimize the danger of transient voltage spikes damaging very expensive equipment when starting and shutting down the engine.

The simple fix is adding an avionics fuse block inline with the Endurance bus with a switch in between.   The EFIS has its own power switch and will remain on the E-bus.  So far so good, and the install went smoothly, except for the time I dropped the passenger stick through-bolt down the hole between the center section ribs.  That was fun, because my fat hand doesn’t fit past the stick through the access hole, and I wasn’t about to take the floor panel off.   I then fished around with a magnetic screwdriver bit holder, and that sort of worked, but then somehow, I dropped that in there too.   After a brief bit of grumbling (seriously, how long can you stay mad being at an airport), I was able to fish that out of there with a couple of long aircraft drill bits held like chopsticks.   After that, I got my bolt back.

I forgot to bring little zip-ties to re-secure the DB25 connector on the pax stick.  Also, I forgot to bring my little screwdriver so I could tighten up the connector on the back of COMM 2, which will get fixed tomorrow morning before work.

So now I’m less worried about blowing up my avionics than I was.  But the process was suspiciously painless, right up until that last bit.

Selfies in Flight

Given all the hullabaloo regarding selfies in flight brought on by this incident, I thought I’d share my thoughts on a few things.

First, the actual flight that crashed had no record of the pilot taking pictures.   That happened on the flight BEFORE the crash, meaning he went up, his pax took a bunch of flash pictures at night in bad weather (not smart), but managed to land safely.  The NTSB is assuming the behavior on the previous flight happened on the incident flight as well.   From the article,. what is evident is that the pilot took off in bad weather at night, became disoriented, stalled the aircraft, and hit the ground at a high rate and angle.   The hubbub is a perfect storm of the NTSB engaging in raw speculation, a public conditioned for decades to fear airplanes, and a popular trend in social media.

Second, after some research (granted, not  much) there is nothing in the Part 91 FARs prohibiting use of a camera in the cockpit, either by the pilot or passenger.   It may be a bad idea in certain situations, but it’s one pursued at the pilot’s discretion, and that’s how it should be.

Aviators go through extensive training and live under the banhammer of the FAA to achieve one primary goal:  The safety of the non-participating public from an activity that we do voluntarily.   It is the duty of the pilot not to subject people or property to unnecessary risk.  Every aviator makes that call on every flight, and the choice to do something or not do something based on risk are what we like to call personal minimums.   For instance, if the airspace is crowded, the radio is busy, or I’m otherwise in a situation of high pilot workload, pulling out a camera is probably not a good idea, and in those situations, taking photos is below my personal minimums.

However, if I’m cruising in an empty sky, in contact with ATC, and at a high enough altitude, I think it’s OK to take a few shots.   After all, it’s the only way I have to share what’s outside my window with all of you.

Update:  I’d like to point you to this extremely informative article by Bob Collins, which says pretty much what I said, except a whole lot clearer and better.

 

 

A Weekend in San Luis Obispo

We’ve been planning to get out of town for a bit, so we decided to head up to San Luis Obispo for a long weekend.   Friday morning, after we were done buying a new car in the hell that is Hamer Toyota, we dropped off the dog with the sitter and headed out.

Above the Pen Mar Golf course at the end of Rwy21

Above the Pen Mar Golf course at the end of Rwy21

After 313TD’s wheels left the earth, the day got a whole lot better real fast.   It was stupid hot out though.   My oil temps were running 220 before we got north of Malibu, so I put the nose down and cruised us for a while to bring it down.

 

Leaving Malibu behind.  PCH below. Surf's up.

Leaving Malibu behind. PCH below. Surf’s up.

We went along the coast for a while, then cut east to get on course for the San Marcus VOR.   In the pic there, Point Dume in Malibu is about middle of frame.

Have I mentioned that I love flight-following?   We picked up a squawk code at SMO and they hung with us all the way.   I went with the San Marcus VOR as a waypoint, because I wanted to stay clear of the mountains and stay near the many airports on the way up there.  It’s an Experimental aircraft.   Every flight is a test flight.

But the flight, once we got to 10,500ft, was smooth and fast.   There was a little bit of chop over the foothills, and the climb lasted longer than I’d have liked because of the oil temps, but it was easy going once we got there.   Fuel burn was about 9gph and we held it to a respectable 182 mph the whole way to San Luis Obispo.

Arrival at SLO

Arrival at SLO

We had some high overcast, which helped, because it eased up the in-cabin temperatures quite a bit for us.  Although, at 10,500ft, it’s pretty chilly.   The RV-7 is a drafty airplane, at least mine is.

Arrival over farmland, SLO

Arrival over farmland, SLO

It’s amazing how a little rain turns everything green.  Greenish.   This will all be brown 3 months from now.  Or on fire.  Take your pick.

On glide path for rwy29, KSBP

On glide path for rwy29, KSBP

On final approach to KSBP, runway 29.   The weather couldn’t have been nicer, and 313TD handled the trip perfectly.

After touchdown, we parked at transient, and the very friendly, very helpful folks at the San Luis Jet Center gave us a ride to the FBO in their golf cart.   We picked up a rental car from Enterprise, which is right there next to the Jet Center.

NOTAM:  If you call and reserve a car, walk the 200 steps to pick it up yourself.   If you have the Jet Center people deliver the keys to you, a $22/day car becomes a $44/day car.

But we stayed at a nice AirBnB really close to town, and we did several of the recommended activities, namely a hike in the Johnson Ranch open space preserve, a picnic lunch on the river in town, a trip to the Hearst Castle (which was awesome), and right before we left, we took a quick walk through the Bishop Peak Trail.   We didn’t go all the way up, that would have been crazy.   Just a quick walk through the woods, where Shelley took this pic:

Hike in the woods before departing

Hike in the woods before departing

I want to live amongst the rocks and trees.

Our day was better than somebody’s:  On our way up to the trailhead, the road was blocked by the Fire Department, putting out a house fire that coated the whole valley in a stream of wispy smoke.

SLOPreflight

Preflighting 313TD before departure

Even with the hike, were were preflighting at 9:30AM, before the heat started.

Making sure no birds nested in my intakes.

Making sure no birds nested in my intakes.

No birds in my cowl?  good.

Departing Rwy 29 takeoff roll

Departing Rwy 29 takeoff roll

Squawk code obtained, cleared for takeoff, RWY29, left downwind departure.

Takeoff Roll SLO 2

Takeoff Roll SLO 2

Winds were calm, and takeoff was nice.   Yes, I could be a little more over the centerline, I’ll work on that, I promise.

Departing rw7 29

Departing rw7 29

These planes really don’t need much runway at all, and with cooler temps, my oil temp wasn’t complaining.

SLODeparture2

Rolling into the downwind at San Luis Obispo

We basically reversed the trip, heading to the San Marcus VOR, then back to SMO.

SLOClimbOut

Another absolutely amazing day for a flight.   In March.  In a t-shirt.  Here we’re looking sort of West-ish, heading Southeast.

Looking West, now south of KSBP

Looking West, now south of KSBP

That’s US101 off our starboard wing.   If we’d taken that, in a car, we’d have spent 3 hours on the road.   Actual flight time there was 53 minutes, according to the flight clock on the transponder, and 57 minutes back.

At altitude it was a little chilly, so we got to use the cabin heat, which puts out a respectable volume of hot air.  The cold draft from the rear of the plane tells me I’m going to be investing in hats if we live someplace cold, but it was definitely workable.

Over Ventura, we did a slow descent from 9500ft to 3500ft, to get in under the LAX Class B along the coast.   But as soon as we dropped below 4500 feet the outside temperature went way up.   Not only that, flight following handed us off to 125.5, and they refused to call us back, which was weird.   I thought my radio may have malfed again, so we pulled out the handheld, but it was just SoCal being rude.  SMO tower heard us just fine.  There was pretty much nobody in the pattern or inbound so they cleared us to land while we were still above the Palisades, which is probably the only time that’s ever happened to me.   Of course, by the time we got into the pattern the temperature outside was 85 degrees, which makes for a sticky, miserable flight if you don’t have AC.

A huge thanks to Shelley for all the pics and for spotting traffic outside the window.

Annual Inspection 2015

Believe it or not, it’s been a year since 313TD was given its special airworthiness certificate.   In that year, I’ve put 65 hours on it, which is respectable.   But alas, no matter the hours, the regs say you have to do an annual inspection.

I won’t bother posting the whole list of items checked, but I did find a few things I wasn’t terribly happy about.

  • Throttle cable got a little too close to the exhaust.  Operation seems fine, but the plastic wrap is bubbled slightly where the heat-wrap runs out.   It also chafes against the fuel pump.   I wired up a fix, we’ll see if it stays.
  • The wires going into the lower rudder cover are a little chafed.   Wrapped ’em up good.
  • Left side fuel vent line fitting was loose.  Blue residue inside the wing root fairing.
  • The screws holding the spinner on were crap.  Two of them stripped out and had to be removed via drill.  Replaced all with 6/32 stainless.
  • Stripped out a mag screw.  Why do they make those things with Torx fittings?   Suck it, Slick Aircraft.   I was able to drill off the screw and replace it with a slotted one like it’s supposed to have.
  • Fuel hose from throttle body to injection spider was loose at the spider.   That’s the only really scary one.  But this is what inspections are for.
  • Left aft wheel pant cracked.   I think I may have jammed a chock under it a little too hard at some point.  I have to fix this over the weekend.

To do the job, I rented some floor space from Andre over at Bill’s Air Center.   Once I got in, I was able to do the job in 3-4 hour chunks, using  mostly my own tools.     The guys there are awesome!   It really helps to have several master aircraft mechanics occasionally looking over your shoulder and helping you out with the hard stuff.   But really, most of the pain is dealing with access panels.   So many screws.    I have a few things left, but mostly I wanted to get out of the shop and give Andre his floor space back.    Here’s what’s left:

  • Adjust Idle.   This is the biggest one.   I re-timed the mags, and it looks like they’re better than the last time I did them, plus with a set of clean plugs, the engine runs way better.   Problem is, the idle is about 200rpm too high, and it stumbles a bit on throttle advance.   I suspect this is because of the change in timing.
  • Fix wheel pant.   Without this, I can’t fly.   That happens ASAP.
  • Reinstall interior.   I took most of it out and left it at home while I was working.   Seemed like the smart thing to do.
  • Fix o-ring on right fuel drain.  Fuel leaks are not cool.

I also fixed a couple of things that were annoying me, like the canopy latch being too tight to allow smooth operation.

So once I get my to-do’s done, I’ll make a logbook entry certifying its airworthiness and take it for a test flight.