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Shadrach

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Everything posted by Shadrach

  1. It’s clear that he had a door pop after departure but that in and of itself did not seem to cause the accident. Tower controller was the portrait of accommodating and professional. I imagine there will be security camera footage of the final moments. Grateful that no one on her ground was injured. RIP.
  2. It’s likely not a risk and presents a fine short term solution in a pinch. As a long term solution, it looks like needlessly deferred maintenance. If a window regulator on my car fails, I’ll duct tape the window shut to keep the weather out until I can schedule the repair. I would not call it a permanent solution. The HV system is well designed and when properly maintained, does not leak from either cold or hot side. The Wemac vent (plum cooler) on the pilot side should not leak air either.
  3. Non pressurized turbines answer a question that no one is asking.
  4. Truth be told the heating and ventilation system is the one of the cheapest and most straight forward systems on the airframe. It requires so little that it is often neglected. Having a properly sorted HV system makes for much more pleasant all season experience.
  5. 1)I don’t know what the metal plate you’re talking about looks like as the earlier birds like mine have a push/pull control with a button lock. Good chance a machine shop could fabricate that part. Just need to remove it to have it reverse engineered. You definitely want filtered air during takeoff. 2) reads to me like your heating and ventilation system needs to be thoroughly inspected. The slider that you mentioned does not have a seal, but it should be fairly precise in its movement, and sit flush against the side of the mixing box. The cable and slider door should be lightly lubricated at annual.. if it’s not closing completely with the cable, someone needs to find out where it is binding.
  6. I covered every part of the interior walls with .5” super sound proofing from Spruce. I also made ceiling panels out of it and covered them in same lightweight ultrasuede that I covered the plastic panels with. I don’t know that it made a huge difference in noise reduction. It did eliminate almost all rattle and vibration from the interior. The interior now has a much more refined and warmer “feel” as all surfaces are upholstered. More importantly, it really evened out interior temperatures in the winter. My bird has a blast furnace of a heater, but before insulating it was tough to keep everyone comfortable in cold temps. You could keep the back seaters warm but at the expense of cooking those up front. It’s much better now, not perfect but if people wear layers, we can keep everyone comfy even at single digit OATs.
  7. Do you still have a compression tool on hand? Whoever does the installation will need to compress the shock discs. I would also look closely at the collar. I am not sure that the bolt hole is centered on the collar. In other words, the dimensions may differ meaning that the geometry of the gear might be affected by on which side of the collar if facing up. Seems odd that installing new, uncompressed discs on would require a spacer when old discs did not. There was not a lot of difference in thickness between my old and new discs but there was some. The new disks were definitely thicker if only marginally.
  8. So then, my sub two hour fill and bleed success was not affected at all by putting a vacuum the reservoir... That's actually good news. Given that I likely spent 30 mins screwing around with different hoses, fittings, zip ties and clamps to adapt the MightyVac to the reservoir, it was actually took just over an hour to do only the stuff that mattered. I guess it is better to be lucky than smart...
  9. I’m being a touch pedantic, but the theory actually counts on the fact that the fuel in the lines will boil out and “pre prime” the intake manifold with fuel almost immediately. You can hear the fuel bubbling, hissing and moving through the lines almost immediately after shutdown. If the plane sits for too long, the fuel vapor that has boiled into the intake manifold dissipates and you are left with no prime and little to no fuel in the injector lines. This is no problem of course as you can just add more using any number methods discussed here multiple times over the last few decades.
  10. Thanks for the explanation gents. I look forward to reading more and doing my own experiments. Should be easy to cobble together some clear tubing to observe the behavior of air in tubing. The reason I employed the tactic in the first place is due in part to my practical experiences bleeding the cooling systems of water cooled rear and mid-engines Porsches. Under those scenarios the reservoir is the highest point, the water pump and coolant passages through the block and heads are clustered near the low point as are the combination of soft and hard pipes traveling all the way to the front bumper through two or three upright radiators (depending on model) with coolant passages much higher than the rest of the plumbing. Using a vacuum to fill and evacuate air from those systems is best practice. indeed Porsche sells a $100 coolant system vac rebadged with their emblem for $500. Trying to fill and bleed without a vacuum system can be a challenge that sometime necessitates jacking the ass end and burping the system by reving the engine. Perhaps the best method for the Mooney is to put a vacuum on the reservoir with the system empty and draw fluid individually at each low point until it reaches the reservoir.
  11. If it starts using the the flood procedure, then it is making spark. That does not mean it is making spark at the right time. You can check idle mixture next time you shut it down by leaning slowly idle rpm. You should see a rise of 25-50RPM as the mixture hits best power on the way to idle cut off. I think this is likely ignition related and would focus on the starting mag (Surefly).
  12. legally airworthy? Sure. It's the tax evasion that is the problem.
  13. I’ve been thinking about this and it does not make sense to me and here is why. I have seen fluids more viscous than hydraulic fluid rapidly degassed befor they cure. A degassing chamber rapidly (necessary given the curing times) is used to remove large and fine bubbles from epoxy resins and silicone. It uses about 1 bar of vacuum to do so. The Epoxy and silicone are significantly more viscous than 5606. Why is it that you believe that hydraulic fluid cannot be degassed by applying one bar of vacuum to the system at the reservoir?
  14. I cannot speak to the M20R but I can say that some of the vintage birds seem to have a high spot between the cylinder and the caliper when resting on the gear. I don't know that this is actually the case, but the sometimes stubborn pockets of air that are challenging to evacuate make it seem so. Rapidly pushing fluid up from the caliper seems to be the best way to drive it out of the system.
  15. Mighty Vac was the last part of the process for me. I was able to get an acceptable amount of peddle just from driving fresh fluid from caliper to reservoir. Putting a vac on the reservoir just made it easy to get the remaining air out of the whole system. The brakes were relatively quick and easy from start to finish. After this last flush and fill, I came away confident that I had dialed the procedure for one man hydraulic system maintenance.
  16. If debris is a concern, the system should be thoroughly flushed. I have never found debris in a an aircraft brake system. I have however found gelled fluid, and it would seem that it is easier to push it out using gravity to your advantage by pushing it out of the low point fresh fluid. This can be accomplished by actuating the brake cylinders with the bleed valve open. As for bleeding a flushed system, it seems counterintuitive to try to try to suck the lighter substance down through the heavier substance. In both of your scenarios you’re trying to suck or push the lighter of the two substances in the system, namely air, down and through the heavier substance, namely hydraulic fluid, and then out of the bottom of the caliper… A pressure pot placed at the caliper pushes fresh fluid in at the low point driving the air up an out through the reservoir. A vacuum on the reservoir creates a low pressure area at the high point providing additional encouragement for the air to move up and out and without sucking fluid into the pump. There may be applications where the process you describe is beneficial, but I can’t see how it would be beneficial for bleeding a Mooney (or most any other GA aircraft). The bleeding procedure in the factory MM is poorly written, but as I read it, it recommend pressure pot at the wheel and over flow tube at the reservoir. The mighty vac on the reservoir technique is mine own though I am sure others have come up with similar methods.
  17. Did you mean Mighty Vac on the reservoir? I cannot imagine putting a vac at a low point in the system.
  18. Farm diesel too! Years ago I knew of a guy in Northern PA that was running a Mig-17. It was rumored that operated almost exclusively on off road diesel. While illegal, I understand why at >200GPH burn rates. The running joke was that Ultra Low Sulphur, farm diesel was likely far more refined than anything the Soviets ever put in it.
  19. This last time I did my brakes, I was alone. Knowing this would be a challenge, I employed the following procedure which worked flawlessly. Tools: Mighty Vac - This is simply a hand pump that draws air out of the system. This inexpensive pump from Harbor Freight or any other brake/clutch bleeder would work just as well. Motive Power Bleeder This is simply a pressure pot the pushes fluid into the system. Any other pressure bleeder would work as well. I have seen garden sprayers repurposed as pressure pots as well. 1/4" AN flare fitting for Hydraulic reservoir. Various fittings and several feet of vinyl tubing in different sizes. Various hose clamps or zip ties. Clean Bucket/Catch can Procedure: Flaps first - Make sure flap lever is in the up position. Attach 4' of clear vinyl tubing to flare side of 1/4" AN fitting and clamp to seal. This will serve as an overflow. Remove plug from fluid reservoir and and thread on AN fitting with tubing. Ensure tubing outlet is in a bucket/Catch can. Fill pressure pot with one qt of Hydraulic fluid. Royco 782 synthetic is superior to 5606 in my opinion. They can be combined if not fully draining the system. Attach pressure pot to the T fitting on the flap actuator with a clamp. This is the lowest point in the system. It is accessed though a small oval panel just ahead of the stub spar. It is a tight space with which to work. Make sure the pressure pot hose is well secured to the fitting and is not kinked. Pressurize pot (30-35PSI is plenty). Get into the plane and watch for fluid at the reservoir overflow tube. As soon as fluid is visible in the hose, begin pumping the flap handle vigorously. You should feel it pulling fluid into the pump cylinder. Exit plane and have actuator T fitting cover on hand. Depressurize pot, then quickly remove hose from T fitting and replace with cover. Clean up hands/remove gloves. Pump flaps do to lock out position and leave them there. Does not matter how many pumps it take at this point Using a straw as a thumb siphon, reduce the fluid reservoir to ~half full Empty catch can into pressure pot move on to the brakes Brakes - Attach pressure pot to bleed nipple on bottom of caliper and secure with clamp or zip tie. Pump pot to 30-35psi Open bleed nipple Get in the airplane and pump the appropriate peddle as fluid is pushed into the system. You will feel fluid enter the brake cylinder. When over flow is noted, get out of plane and close the bleed nipple. remove pressure from pot and disconnect from caliper. Repeat process on other brake circuit Using a straw as a thumb siphon, reduce the fluid reservoir to ~ half full Attach hand vacuum to reservoir. This can be done using the vent on the top of the reservoir or the fill opening; it does not matter which but the other will need to be blocked so it is air tight. Draw the system down to 20- 25inHg and position the pump so that the gauge can be seen from the cockpit Raise deployed flaps while system is under vacuum. Actuate flap handle (lever in up position) and brake peddles from cockpit while system is under vacuum. Release vacuum and test systems. Repeat if needed Remove pump, unblock reservoir vent and go fly. Notes: Not all hydraulic reservoirs are the same. Depending on year, some are welded aluminum cylinders with AN fittings and some look more like a repurposed solvent container. The person servicing the system will have to procure the correct fittings to work with the installed cylinder. Either flaps or brakes can be done independently without doing the other. I personally prefer to start with flaps when doing both. It may take a few days for all of the air to vacate the flap system. The best way to facilitate the process is to pump the flaps 3/4 down and leave them for a day (or a week). If a freshly rebuilt flap pump is being installed, fluid will travel more easily through the system with the retraction speed adjustment screw backed out to max flow. This is not necessary, but may make the process easier. Conversely, if the retraction screw is inadvertently tightened all the way down, fluid will not flow through the system. I welcome comments if it appears I have left anything out.
  20. It is a PITA for first timers and sometimes seems to stump seasoned Mechanics as well. A lot of the time it boils down to not having the right tools for the job, sometimes there are assembly problems with a rebuilt pump (I've run into this twice in the last 6 months). However, I system that has had no maintenance other than a drain and flush should be fairly easy to return to service. The reason I suggested the vacuum hand pump is because it will eliminate air from almost all of the system pretty quickly. The exception being the pump cylinder, The last bit of any air trapped in the pump will have to work it's way out. I was not bragging, I was merely posting what is possible when one has the right tools and processes for the job. I was working alone and took the system from full of fluid, to full of air, to full of fluid in under two hours. It is not rocket science, but small details can impede success. If the flap pump has been removed and rebuilt, that adds another area of potential problem. In the last six months I have encountered two different aircraft that have had what seem to be improperly serviced flap pumps (both pumps serviced by MSCs, though I don't recall which) installed. Full disclosure, I was not on site for either situation. In one case the pump was returned to the MSC for warranty repair. Post warranty reinstallation went flawlessly. In the other, I sent them a pump that I had on the shelf and they were able to coble together a working pump by "Frankensteining" them together.
  21. What kind of issues? I just did a drain and flush replacing the 5606 with Royco 782 Synthetic. I'd estimate it took me a little under two hours total from drain and flush then fill and bleed the flaps and brakes to completely solid. It's pretty straight forward. If he can't get all of the air out, he should consider putting a vacuum pump on the reservoir.
  22. Most nose wheel aircraft are poorly configured for hand propping both in terms of prop index to compression stroke and the fact that engine sits lower when on a nose wheel. I once watched an old timer hand prop a twin Comanche in front of a restaurant. It looked so bad that I asked him to stop. He grumbled something like “thank you but mind your own business”. He got it started in two pulls, got in, started the second engine and departed. I thought for sure he was going to stumble right into the prop arc.
  23. Yup and yet…they still get away sometimes.
  24. Might have been me. Do you currently need one?
  25. Why not chock both wheels? Rope is cheap. Having an extra long piece for the left chock makes it easy to pull without leaving the right side of the plane. I realize lots of folks chock just the right wheel. But if you miss set the throttle, the plane is going to pivot around and jump a single chock. I love Martha Lunken’s writing. However it is clear that she came up in a different era of aviation. She has had some incidents that have left me thinking that she’s exercising the kind of decision making that would have been mainstream in say, 1971.
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