Cam

Interesting note - Thanks to Kortopates I did the calculations for TAS at various altitudes and found (assuming Standard lapse rates ) .... if you take a straight line DECREASE in IAS from 81 MPH to 72 MPH from SL to 10000, you get a (close) constant of 82 MPH TAS . This might make you think that the text and the performance chart match, but the performance chart says CAS is the constant 82 MPH, and since the CAS and the IAS don't vary (significantly - 1 MPH at 80 MPH), I'm still left with the same questions.

Thanks Greg!

HI Kortopates, Thanks for thoughts. I totally agree that there is usually no reason to climb at Vx, and climbing at Vy +10 or +20 is better for many reasons. Also agree on you should never depend on Vx in the mountains. All that being said though, there should be a specific value for Vx. As a pilot I should know that speed. I should know that speed and the factors that influence it, and I should especially know that speed if I fly in the mountains even as I do every thing to avoid having to use it. That Vx may change depending on configuration or altitude, and in fact all of the literature I can find says that the speed of Vx 'should' increase as altitude increases. (I think I have that right). My problem is that I seem to have the POH giving 1. A conflicting DECREASING trend on one section, and 2. A constant in another. Both of these instructions/values seem to fly in the face (see what I did there? ) of the Vx explanations and other POHs that I've read so I'm wondering why? As well, I did actual check the CAS vs IAS chart and the speeds are the same except when using 15 degrees of flap and then 79 MPH CAS reads 80 MHP IAS I'm just totally curious now.

I know huh? - hence one of my questions!

Jay - Yes I checked again and it says Vx DECREASING with Altitude. I've included a picture of the manual page. (Middle of the CLIMB section) Skydrv - Yes the M20G and F have same body but a different engine. Mine is normally aspirated (hence the lower Gross Weight) and your F is fuel injected is it not? I'm not sure sure why the difference as I would have thought the same air frame would have the same flight dynamics. Maybe more HP allows a higher angle. I've included my performance chart that says Vx is 82 mph as a constant with altitude in the GEAR UP and FLAPS UP configuration.

My thought process, and I will admit it's not always the best , is that in the west here, you COULD get caught in an approach to a mountain pass, box canyon or something similar (I'll leave it to the reader to look up all of the NTSB reports on these particular scenario's and how to avoid, but ...). At that point, I would REALLY want to know my Vx and if it varies with altitude or configuration or if it is a constant. Hopefully this is a scenario that one would do your best to avoid and to get out of some other way (Turn around for example!)

Hi all, I just had a question for the group to see if this was a common 'feature' of the Mooney POH. I'm a new owner of a 1969 M20G and was reading the POH to find out what my Vx, Vy would be at KSLC (4200'). I looked in the performance section and found a table (in my POH, on pp 6-5) that listed various Rates of climb in Feet per Minute(FPM) and Miles Per Hour (MPH) against Altitude. It also had one column of Best Angle of Climb in MPH against Altitude. It took me a while to notice but the best angle of climb speed was the same, at 82 MPH, for every altitude from Sea Level (SL) to 13000 feet. In my head I thought that made sense as pressure decreases with Altitude and the speed(over the ground) for angle of climb would increase as my altitude increased etc. Not well thought out I know, but being lazy I didn't think about it further. Today I noticed that another section (under 'CLIMB' on pp 3-14, NORMAL PROCEDURES section) of the POH has this quote in it "The speed for maximum angle of climb (for obstacle clearance at full power, gear down, and flaps set at TAKEOFF) is a straight line variation from 81 MPH IAS at sea level to 72 MPH IAS at 10,000 feet." Well, I thought to myself, that doesn't jive with what is in the performance table! What the <insert expletive of your choice here>. Went to google and started a little research on Vx and how to calculate etc. Found a good article (IMHO) here. (http://cospilot.com/documents/Why Vx and Vy Change with Altitude.pdf). SO my question - The only difference between the two recommendations for Vx is that in the performance table, the conditions are enumerated to be GEAR UP, FLAPS UP and the speed for Vx is a constant 82 MPH without variation for altitude, while in the NORMAL PROCEDURES the conditions are defined as GEAR DOWN, FLAPS SET FOR TAKEOFF, and then Vx is a variable speed between 81 and 72 MPH. - What speed do I use? Is the performance table set to 82 for best cooling or something? Do different configurations affect the variable speed of Vx? Why is Vx variable in one configuration and not in another when it would seem to me that Vx should just vary with altitude. What am I missing here? Cheers Cam

Yes Bob's article is very good. I've read it before but it contains some interesting things. For example . "FAR 23.233 under “Directional Stability and Control”. Here is what that regulation states related to crosswinds: 23.322 Directional stability and control A 90 degree cross-­‐component of wind velocity, demonstrated to be safe for taxiing, takeoff and landing must be established and must be not less than 0.2 Vso." So this says to me that for my M20G (Vso of 61 mph) the minimum crosswind component that it should be able to handle would be .2*61=12.2mph (10.6 kts). Further Bob goes on and says "From this testing, I think you will find a common consensus of test pilot opinion that most Mooneys can be operated in 90 degree crosswinds up to 15 knots with an acceptable level of pilot workload. 15-­‐20 knot crosswinds can be handled, but require a much higher level of pilot proficiency and skill in crosswind landing techniques. 20 knots or above, you should consider finding find another airport to land." "As with all approaches, optimum approach speed in crosswinds with full flaps is 1.3Vso (stall speed in the landing configuration, gear down and flaps full down). That’s the number generally shown in the Owner’s Manual or Pilot’s Operating Handbook. If there is a higher number shown in the POH, use it. If it’s gusty, add 1⁄2 the gust factor to the approach speed, but no more. Too fast and crosswind landings can become more difficult."

Late response to this topic, but I was just reading an article todo with cross winds since I was out yesterday in some (to me) breezy and gusty conditions 18018G24KT, and wanted to do more research into my rusty crosswind landings. Now, just to be clear, I'm a sniveling coward, so I only went out because I really needed to get my ADS-B flight test done and I had a 10,000' runway oriented at 170 so the actual cross wind was almost 0. (Now ballooning, because of a gust (I hope) ... that was fun ... but this is about cross winds. ) Anyway, the article had an interesting suggestion that I hadn't thought of .... "Not long after I got my private rating, I learned one other technique for handling very strong crosswinds. It is perfectly legal but rarely considered. It has prevented accidents, yet airport managers sometimes get distressed about it: If the airport has a long enough taxiway that is oriented into the wind, isn’t near buildings or obstructions and there is no one on it, you land on the taxiway. As long as there aren’t any people or things to hit, it’s certainly much safer to land on a taxiway that is into the wind than try to land in a crosswind that is so strong you are concerned about your ability to make a safe landing. The Federal Aviation Regulations contain no prohibition against taxiway landings. So long as the landing does not conflict with any other airplanes and there are no people, vehicles or buildings in the immediate vicinity of the touchdown and rollout area, the operation is not careless or reckless, and is far, far safer than losing control of an airplane while landing on a runway. You may never need this tool in your bag, but stick it there, just in case." (Article at Avweb) Maybe food for thought.

Right. . ADLOG does provide paper forms to list all that information and then you can have it all in one place.

.... in "the system" - do you mean ADLOG?

Yeah, I've seen an ADLOG log and it looked very organized. Being a software guy I was hoping that there was something online that I could enter all the serial numbers, part numbers, manufacturers, etc and have it spit out a report. It just strikes me that this is just data. Maybe I'll take a look at it and maybe see how hard it would be. (Probably extremely, which is why no one has done it! . ) Not going flying today anyway .... KSLC 201854Z 34017G28KT 5SM HZ FEW025 SCT050 OVC110 13/00 A2979 RMK AO2 PK WND 28040/1801 WSHFT 1741 SLP051 VIRGA OHD AND SW-NW SH DSNT SW-NW T01330000

Yes, that seems to be the way most people do it. I did find a 'summary' sheet of all the AD's that had been complied with for the plane. That was further split out into Airframe, Engine, Prop and Appliance ADs which I thought was good of him. But there were a couple of problems with it; 1. It was from 2007. 2. When I got the 'Current AD' List from the FAA website for my "Mooney M20G" , the list contained several that were from before 2007 and where not on the summary list. It turned out that those were all not applicable due to PN or model number or something like that, but it was a pain to go through and open each AD, open the pdf, read the section on applicability, Find in the log or somewhere what the PN or identifying number was and then figure out based on the PN or whatever, that this AD does not apply. THEN - I would guess that I need to add a new sheet and list all the ones that did not apply so the next person who needs to go through this doesn't waste time. It's almost as if you have to have a way to check every single AD as applicable or not, but once an AD could be remotely applicable, it becomes a pain to go in and figure it out. Lesson learned for me is to keep a detailed list of all equipment, Serial Numbers, Part Numbers, Where you got it, Who has repaired it, etc. 3. More on the detailed list .... It would be nice if you could search or filter the AD list based on Part number or Serial Number etc. For example, Lycoming had a "Current AD" that applied to a certain type of Cylinder as well as a specific series of Serial Numbers within that type (Manufacturer). Luckily, I found some yellow tags at the bottom of the log box that had the information from the most recent rebuild and could confirm that the AD did not apply. That one would have been a pain to confirm without those! I'm a software guy and the whole process seems .... manual.;) ... and a huge time suck when I could be out flying! Thoughts? Cheers Cam

Hi All, So I just went through an exercise in taking my new (to me) mooney and reviewing all the logs for AD compliance as well as all the other maintenance items such as ELT batteries, VOR checks, Transponder, etc. I wanted to do this to convince myself that everything was ok. I found 1 AD that was past due (a month) and one that was due in 11 hours and then need to check the new AmeriKing ELT AD when I get out to the hanger because I could find no where in the logs where it noted what kind of ELT was installed. All of that aside, I was wondering what the best way was for a pilot to track all of that. I've looked at ADLOG and that looks good but it just seems like a fancy filing system. I checked out TData - an application for mechanics but they want something between $300-$700 a year. There is Zook Aviation and their product "AD Toolbox" but they want about $50/month. I also found Quick Aviation but wasn't able to find out anything from their website really. (It kind of looked abandoned). I find it hard to believe that there is not a simple online application that would do this for you (at a reasonable cost). I was wondering what other's experience was? Anything that you have discovered that has helped you other folk keep track of ADs, maintenance periods, etc.? Cheers Cam

Hey All, I'm just preparing for my first oil change in my M20G and was looking at filters etc. Had a couple of questions though! Firstly, I was looking around and it seems like the Champion (CH48110-1) should do the trick, what do others use? Secondly, I know that on a car you just do the filter finger tight or 3/4 turn after snug etc. HOWEVER I thought I should look up the correct torque value for a Lycoming O-360 and looked it up in a couple of places. According to http://rvplane.com/pdf/XP360_OverhaulManual.pdf the correct torque value for a "Spin on Oil Filter" is 196-212 (in-lbs) (Yes when I first read that I assumed ft-lbs and freaked but then I read the column heading = 16.33 - 17.67 ft-lbs). This is close to "The filter should then be turned with a torque wrench until a torque of 18-20 foot pounds is reached. The 20-foot pound maximum torque should not be exceeded." found at https://www.lycoming.com/content/tips-changing-your-spin-oil-filter. Both places recommend using "a thin coating of Dow Corning Compound (DC-4)" on the gasket before installing. When I looked it up on Aircraft Spruce and Amazon, they both say it is a Dielectric compound. Presumably what the 'DC' stands for. Has anyone ever used it? Any advantages over just using clean oil? Cheers Cam