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Re: [Jan 4, Sat 7:15pm PST] KNYL - KSNA (IFR @ 150kts)
Posted: Wed Jan 01, 2014 2:24 pm
by Keith Smith
Very good. If you're flying an aircraft with a constant speed prop such as the Baron, have a look at the manifold pressure you get during your takeoff roll (should be about 30") with wide open throttle. Then, compare with your manifold pressure with wide open throttle up at cruise altitude. For a really dramatic example, take the number that you're seeing at high altitude, then next time you're on the ground, run the engines up to that same manifold pressure and note the throttle position.
Here's an excellent series of articles on engine management by John Deakin:
http://www.avweb.com/news/pelican/18254 ... directed=1
Highly, highly recommended.
Note: all of this applies to NON turbocharged engines. Turbos are a different beast...they fool the engine into thinking they're at sea level all the way up to the critical altitude.
Re: [Jan 4, Sat 7:15pm PST] KNYL - KSNA (IFR @ 150kts)
Posted: Wed Jan 01, 2014 9:55 pm
by dc8flightdeck
We may have some military aircraft in the area when you depart. That should spice it up for you.
Justin
Re: [Jan 4, Sat 7:15pm PST] KNYL - KSNA (IFR @ 140kts)
Posted: Wed Jan 01, 2014 11:31 pm
by Mark Hargrove
Keith Smith wrote:What was your mixture setting, and it is a turbo or normally aspirated aircraft?
Normally-aspirated Baron, and I think you may have nailed the issue. I've not had a chance to fly the Baron again today, but I'm about 99% convinced this has to be the problem. According to the POH for the Carenado Baron, if you leave the mixture in the full-rich position it's supposed to auto-lean. I strongly suspect it didn't do so.
I did try the first segment of the flight in my normally-aspirated Cessna Skymaster (which definitely requires manual leaning) and was able to maintain a 500 FPM climb or better all the way up to 10,000', at which point I was able to cruise at about 162 knots GS (was about 140-ish KIAS). I don't know what my TAS was...
...which surfaces an interesting question: neither the stock nor Carenado version of the BE58 have anything that displays TAS, and the "conversion dial" on the outside of the airspeed indicator that let's you do this in the real airplane is inop in the simulated airplane. The only reason I know my TAS numbers from my first flight is that I was using the new Flight1 Technologies G1000 cockpit for the Beech Baron -- it does have a TAS display.
If everybody is flying at the same time and altitude, wouldn't a target airspeed in KIAS be easier for us all to synchronize?
-M.
Re: [Jan 4, Sat 7:15pm PST] KNYL - KSNA (IFR @ 150kts)
Posted: Thu Jan 02, 2014 10:32 am
by Heavyflyer767
Cyrus,
I'm confused. I just checked in the FSX a/c specs. on the default list of available Barons, it has 300hp per engine and cruises at 240kts. with a service ceiling of 30000. I am going to test flight it. (Haven't ever tried it before) . Loadout at 3 pax. and 100gals. fuel., time to climb to 12000.Leaving KNYL at today's temps.Don't mean to make this an excercise but I am curious about the flight modeling of default a/c in FSX. After this flight, I see that the is some discrepancies of the flight model. Even though IO-550 is non-turbo, given my lighter TO WT. numbers should be better. For what it's worth Cyrus.
16 mins. to 12000
min. airspeed 119kts.@11000ft.
19.3 MP
2150 RPM
OAT 1C
Cruise airspeed @ 12000ft. was 149kts.
Re: [Jan 4, Sat 7:15pm PST] KNYL-KSNA (IFR / 10k / 130 KIAS)
Posted: Thu Jan 02, 2014 11:28 am
by Cyrus
Pat, without a pressurized cabin, I'm not sure how long I'd want to be at 30,000 feet anyway

. Oh, and you're not the only one confused by all the comments about the models, types and performance. Having said that, I routinely get 200 to 205 kts GS in the FSX Baron at 10k (confirmed by simply bringing up the default/built-in FSX GPS with SHIFT+F3 - although I try not to use it for situational awareness).
Mark, to your point about KIAS vs GS, I'd estimate that a GS of 150 kts would be in the 125-130 KIAS range (at 10k). If you agree with that number, I'll be happy to add a small parenthetical on the original post, or even update it with "~130 KIAS" and be done with it.
By the way, now that I think about it, I'm starting to feel that I meant "GS" on here every time I used "TAS". If the winds aren't roaring on Saturday, then hopefully the two numbers will be about the same anyway.
This speed and performance discussion has been very interesting, although all a little over my head. Next time, we're all going in Microlights !

Re: [Jan 4, Sat 7:15pm PST] KNYL - KSNA (IFR @ 150kts)
Posted: Fri Jan 03, 2014 3:15 am
by Mark Hargrove
There are three ways to measure your speed -- indicated airspeed (which you read off your airspeed indicator), true airspeed, which is indicated airspeed corrected for static air temperature and pressure altitude, and ground speed, which is your speed relative to the ground. Only one of those can be directly measured in a /A equipped aircraft -- the indicated airspeed. If you have GPS aboard you can also directly measure ground speed. If you have the right kind of flight computer and the right sensors you can calculate true airspeed (but curiously, I don't think you can directly measure it).
My point is just this: the simplest way to get everybody cruising at the same speed is to fly at the same altitude and use indicated airspeed. No special equipment needed, no calculations, no worrying about temperature and pressure altitude -- just read it off the airspeed indicator and adjust your power until you see the number you want. This approach won't work if folks are at different altitudes, but it works great if everybody is at the same altitude.
Using ground speed is probably better (in a general sense), assuming everybody is /G or equivalent and has a means to fairly accurately measure the GS -- then altitude doesn't matter.
Re: [Jan 4, Sat 7:15pm PST] KNYL-KSNA (IFR / 10k / 130 KIAS)
Posted: Fri Jan 03, 2014 8:47 am
by Cyrus
dc8flightdeck wrote:We may have some military aircraft in the area when you depart. That should spice it up for you.
Justin
Justin, I love spice. In fact, the spicier the better. Bring it on.
Mark Hargrove wrote:
My point is just this: the simplest way to get everybody cruising at the same speed is to fly at the same altitude and use indicated airspeed.
Mark, thanks again for taking the time to share your knowledge and experience. Also, it's a good time to mention that I'm a big fan of your videos too. They compliment the PE training videos well, especially your V-3 flight (which I keep watching over and over - and I'm almost ready to fly the whole thing in one fell swoop) and your aptly-named PE "First Flight" video (the first PE related video that I watched... on that fateful December
evening, back in 2012 - which gave me the confidence to try the flight myself). Anyway, I digress...
So I updated the subject line and the original post to reflect a
speed of 130 KIAS @ 10k. Hopefully, that should do it.
Re: [Jan 4, Sat 7:15pm PST] KNYL-KSNA (IFR/10,000ft/130 KIAS
Posted: Sat Jan 04, 2014 5:39 am
by Jack
Great discussion. I fall under the IFR newbie category however I think I'm comfortable participating flying the Cirrus SR22. See you there, hopefully I can keep up!
Re: [Jan 4, Sat 7:15pm PST] KNYL-KSNA (IFR/10,000ft/130 KIAS
Posted: Sat Jan 04, 2014 9:52 am
by Cyrus
Jack wrote:I fall under the IFR newbie category
Me too
Jack wrote:I think I'm comfortable participating flying the Cirrus SR22. See you there, hopefully I can keep up!
Yes, I'm sure you'll be fine. Although might be best if all the single engines (paging Beyoncé) head out first.
Re: [Jan 4, Sat 7:15pm PST] KNYL-KSNA (IFR/10,000ft/130 KIAS
Posted: Sat Jan 04, 2014 3:45 pm
by Mark Hargrove
Cyrus wrote:
Although might be best if all the single engines (paging Beyoncé) head out first.
LOL!