Why are we not talking about this...

[snglecoil 1,828]

Depending on how the program models wind in a cloud, I can see that having an impact on ground speed. I’ve done a fair bit of instrument flying an out of clouds and can’t say I’ve ever noticed any difference in indicated airspeed.

[cwburnett 1,809]

2 hours ago, jpe828 said:

Didn't meant to trigger with a "clickbait" title, genuinely curious why no one is talking about this. There is no explanation. 

I admit I've been heads down coding and hadn't taken many full flights in a few months, but I noticed just this morning that I was having trouble holding climb performance in clouds and since we built a custom FADEC for the CJ4, I immediately suspected a problem there. After some digging I decided it must be overdone icing and put it on my mental Asobo list.

Then I saw this thread, decided to give it a go in warm air...sure enough you're dead on. No explanation.

For ease of development I do all my testing in clear days and ISA temps and std pressure...so never saw this in months of testing...

Thanks for raising it. This is now on my Asobo list. 👍

[HighBypass 2,339]

13 hours ago, Stona said:

Perhaps a real pilot can share there lived experience flying into a cloud and resolve this discussion!

Er... He just did share his experience in the post above yours and his username is G550flyer !! 

Other AVSIM members who are also real world pilots are available too.

[HighBypass 2,339]

12 hours ago, Chock said:

You can try this for yourself to see how sensitive to pressure changes a real pitot tube is if you have access to a small GA aeroplane with a speedo which is calibrated to a typical 100-ish knot range

Even easier than that if you're in a glider as no doubt Chock will attest to. Sitting in a K13 and K21 (I was fortunate to have time in both), going through the checklist and eventualities, I could see the ASI needle wavering from its stop as it was picking up the gentle gusts of wind.

[G550flyer 1,013]

14 hours ago, Chock said:

But as an interesting aside, a pitot tube is indeed incredibly sensitive in reality. You can try this for yourself to see how sensitive to pressure changes a real pitot tube is if you have access to a small GA aeroplane with a speedo which is calibrated to a typical 100-ish knot range, and this is in fact how you test if a pitot tube is okay on a walkaround (if you have two people): Get the palm of your hand and place it gently over the opening end of the pitot tube

Here is a funny oof I have had with pitot and static pressure. One day in the DC10 I was passing transition and was lazily leaning against the altimeter setting knob while dialing in 2992. We hit a bump which caused me to lean even harder onto the settings knob. The jet immediately pitched aggresively as we were climbing in IAS mode(FLCH). I guess it caused some cabin air to enter into the system. Since then I try not to put any pressure on that knob when changing settings lol.

[bobcat999 8,480]

1 hour ago, G550flyer said:

Here is a funny oof I have had with pitot and static pressure. One day in the DC10 I was passing transition and was lazily leaning against the altimeter setting knob while dialing in 2992. We hit a bump which caused me to lean even harder onto the settings knob. The jet immediately pitched aggresively as we were climbing in IAS mode(FLCH). I guess it caused some cabin air to enter into the system. Since then I try not to put any pressure on that knob when changing settings lol.

It's great to hear these real world experiences.  That situation is something I never would have thought of.  😁

[Ajb376 59]

I'll chime in as a real world GA pilot and previous owner of a bonanza and current owner of a Baron. Short answer is, no, definitely would not cause this type of airspeed change that you might be seeing.

Longer answer is that there is nuance, but here's what I'll say. Whenever I am entering a cloud that I might feel is a bit more "traumatic" than a gentle bump, I pull back the manifold pressure (throttle) to about 19 inches and get as close to Va (maneuvering speed) as possible (with the exception on climb-out, so this is cruise fyi). If I'm in autopilot mode, I tightly grip the yoke and my hand is on the throttle the whole time I'm in IMC. While I am still scanning my instruments I zero in on two things...the attitude indicator and airspeed tape on my G500txi. My airspeed will start fluctuating up and down +/- 5 knots if I'm in some light chop. The wind on the pfd will start to fluctuate +/- 20 degrees and vary in speed too. If I need to pull from the autopilot, I'm in position to do so and can hand fly the plane. If its a long period of IMC, usually I am relaxed, but I can't say that I haven't "death gripped" the yoke before. If there is an hour plus of IMC, I am usually exhausted by the time I land. 

If it is moderate to severe turbulence...oh boy. It only takes one time to make a wrong turn into a cloud that you should never have gone into to say "nope, never again".

For me, it was on my very last flight in the bonanza from Philadelphia to Dallas.  A squall line diagonally covered the US stretching from Arkansas to Pennsylvania. I was about 30 miles to the south of it flying parallel "thinking" about where I could cut in (NEVER do this) when I thought I'd test the waters with a "gentle" build up in front of me that I went through.

Dropped 1,000 feet about 10 seconds and my airspeed went from 150 to 180 to 130 in a blink of an eye. Immediately landed in Knoxville and changed my pants.

I avoid thunderstorms at all costs. I'll skirt around summer build up (and even go through if its early enough in the morning and hasn't caught the afternoon pop up thunderstorm, but nope, never again. 

[WestAir 2,522]

1 hour ago, Ajb376 said:

I avoid thunderstorms at all costs. I'll skirt around summer build up (and even go through if its early enough in the morning and hasn't caught the afternoon pop up thunderstorm, but nope, never again. 

One thing that always killed me about flight sims was how gentle the extreme weather was.

Even in MSFS you can fly through an anvil and come out the other side just fine.

I'm waiting for the weather update that adds bird sized hail, microbursts, mountain waves and these twister clouds:

[G550flyer 1,013]

29 minutes ago, WestAir said:

One thing that always killed me about flight sims was how gentle the extreme weather was.

Even in MSFS you can fly through an anvil and come out the other side just fine.

I'm waiting for the weather update that adds bird sized hail, microbursts, mountain waves and these twister clouds:

Storms in flight sim get no respect🤣

[Ajb376 59]

21 minutes ago, WestAir said:

One thing that always killed me about flight sims was how gentle the extreme weather was.

Even in MSFS you can fly through an anvil and come out the other side just fine.

I'm waiting for the weather update that adds bird sized hail, microbursts, mountain waves and these twister clouds:

Totally agree. Weather in MSFS is just under-appreciated as a flight planning mechanism (can't speak for the other flight sims). In the real world, I probably spend 75% of my time planning for the weather if I'm going on a long cross country. If the route is familiar...its closer to 90%. Just look at how broken Nexrad is in the sim to understand my point on weather (shows cloud coverage vs precipitation).

Cloud coverage, winds, icing, thunderstorms, ceilings, temp, all have dramatic effects on the flight on departure, en route, and arrival/approach. MSFS looks beautiful but its a bit of a static eye candy imo.

For real flight planning I use Windy (Big Picture), Weatherspork (route and timing), Takeoff (METAR and TAFS at local fields), SkewTLogPro (technical information about packets of air and the potential for TStorms), Garmin Pilot (onboard radar, nexrad, and ADSB).

Those are all just weather. For actual route planning I use Garmin Pilot (but thats a snap...NOTAMS and TFRs are what I'm watching for) and Baron Performance (Weight and Balance + airspeeds).