With regard to the carb icing, the determining factor is humidity not outside temperature. Hot humid tropical weather is renowned for causing icing issues.
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I might be wrong but from what I can see the Authentikit controls aren’t actually verniers - IE you can’t twist the knobs for fine tuning. So sliders (coarse adjustment) only.
To be honest I hope I’m wrong because the kit you can buy via Sim Kit Supplies looks really nice.
Apologies, vernier style.
You can get pretty fine control without the true vernier if the shaft has a nice smooth action and good quality sensing. Sure it’s not the same as a true vernier adjustment but for that you need to hunt a bit deeper into more niche products and pay quite a bit more money.
Flying from UHMM Sokol to UHMW Severo Evensk in live weather today - with a varying headwind. Obviously very cold OAT of about 9F. After about 50 miles I noticed that my airspeed had dropped from 160mph to about 75. I checked everything and found nothing wrong, but …the GTN750 & Little Navmap showing about 140knots. I carried on and eventually landed OK with airspeed showing about 65-70mph on approach, and the GTN750 showing 95knots. Also I noticed that the A2A tablet had stopped showing the wind direction and speed (and cabin temp). I did the 313 miles in 2.5 hours which is an average speed of about 125mph. All very odd - was this just a fault with the airspeed indicator? Or something I need to learn about headwinds? Your thoughts appreciated.
Did you turn on the pitot heat?
Yes, I mean to add that to the post. Pitot heat switched on
Did the pitot heat circuit breaker trip — either on its own or by accidentally being clicked?
(Clicking these by mistake is pretty easy to do, ask me how I know…)
Indicated airspeed, true airspeed, and ground speed are all affected by different things.
Indicated airspeed (IAS) is the dynamic pressure measured by your pitot tube. This is read on your airspeed indicator.
True airspeed (TAS) is IAS corrected for altitude and temperature. This can be derived with a flight computer, AHRS, or an adjustable window within your airspeed indicator.
Groundspeed is TAS corrected for the motion of the fluid that is atmosphere (basically a direct measurement of your speed over the ground as affected by a headwind or tailwind component). This is read directly off your IRS, GPS, ATC radar, or a DME (with some geometric limitations).
It’s very possible that your groundspeed was being affected by a strong headwind.
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Tell me if I’m not explaining this well, I only have part of a PPl’s worth of training.
But I think a good if a little oversimplified ELI5 explanation for the various speeds is IAS is how fast the pitot measuring your speed thinks you’re going through the air, TAS is how fast you’re actually going through the air, GS is how fast you’re moving over the ground. IAS is most important even though it’s usually wrong because the changing pressure of the air is what is making the IAS read incorrectly, however that pressure has the same ratio of effect on both lift and airframe stress, so as far as airframe limits on one side and stall speed on the other side, IAS is what matters even if it’s incorrect. GS is telling you how long it’ll actually take to get to your destination. Crucial for knowing your fuel situation(or bio situation for IRL GA flying).
At the end of the day TAS is relatively unimportant although still a useful datapoint. For critical information IAS tells you when you may hurt the aircraft or stall the aircraft on either extreme. GS tells you how long it’ll take to get there and most importantly if you have enough fuel to get there or enough …capacity… to get there or if you need to find an alternate place to land and refuel or take care of your code brown.
You’re pretty much right. Operationally, IAS is how you fly the plane (until you start getting into Mach).
However, the effect altitude and temperature have on TAS is pretty important. We don’t always have a GS readout or we might be maneuvering a lot, so being able to consider the effect an increased TAS has on our resulting GS (before we think about wind) is pretty significant, especially at higher density altitudes.
So I don’t throw away TAS as a mere datapoint - you have to know what that is (or is going to be) before you can plug in winds to get your ultimate GS and it will really mess with your climb/descent angles, pattern geometry, obstacle avoidance, takeoff/landing roll, and how that all looks visually.
And yes, GS plays in heavily to ultimate range and planning stops (and other ancillary things like weather avoidance).
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Thanks, good to know! It sounds like you’re a commercial pilot of some sort flying jets? Again really at the beginning of my journey actually flying planes, all of my flying experience, at least as far as being involved in the process and not just a passenger, is short flights in 172s and a buddy’s Comanche all just steam gauge and basic GPS, only one single time even having been front seat in a plane with a G1000. Longest being 3-4 hours out and back to a massive dry lakebed(not the Black Rock desert, but exactly like that) to do a couple flyovers, I guess a couple hundred miles total in the Comanche where my buddy that does fly professionally was 100% running the show and PIC, not an instructional flight just a fun flight, although he did teach me about what was happening and let me fly during some of the flight. Question I’ve been leading to with all that being, and if it’s not something you feel like typing out now I’ll ask him too next time I see him plus ask at my next lesson, was my buddy calculating TAS on a medium length XC flight like that and using it for something as we went, or for relatively short and slow VFR flying which is really all I want to do IRL as a hobby, no aim to be flying commercially personally and do plan on doing the training for an IFR rating but more for safety’s sake than any real intention to do serious IFR flying, is it just not something you have to worry so much about? And if it is something I should be learning to calculate as I go more specifically how should I be using it? Assuming something like a Comanche or Bonanza is as high performance as I’d ever end up flying solo, if even that.
All of what he said is what pretty much every pilot needs to know and thinks about. IAS, TAS, GS; I’m pretty sure it’s all knowledge you need to know for the PPL exam.
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It’s definitely all knowledge that is required for PPL. I’m not sure how relevant it is beyond that point, especially in today’s environment of electronic navigation aids. It would certainly all still be important if a person flies using charts and dead reckoning or ends up flying an aircraft without sophisticated electronic navigation suites.
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Very relevant. We have to imagine scenarios where electronic navigation has failed.
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There are a lot of wrecks out there that can attest to a lack of appreciation for how density altitude affects all three airspeeds. All the fancy gadgetry in the world can’t help you if you grossly underestimate it.
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Hi guys, Xbox user (i know buuuuh) but a Question if you dont mind: is the pms50 750 navigation unit available with the commanche on Xbox like the flysimware 414? Or on pc “standard”? Or does this needs to be downloaded seperatly?
Thanks for any answer in advance.
Best regards
Sorry, I don’t know the answer to your question, but I am wondering what’s wrong with being an Xbox user? Nothing wrong with that. I think it’s a great platform.
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It is not available at the moment like the 414 and cannot be downloaded separately.
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Causes black screens and when working massive LOD issues like I’m flying FSX when in the 414.
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