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ken nougaret
01-12-2014, 06:47 AM
i'm in the market for an airspeed indicator for my ss7 under construction. so far, my other instruments are falcon. is kitfox talk usually in mph? what kind of max speed should I look for, 140,150,160? and I'm thinking its best to have one where the numbers have a good spread to them past 30 (not crunched together).
thanks, ken

SkyPirate
01-12-2014, 09:16 AM
Mine goes to 160 mph

Danzer1
01-12-2014, 10:53 AM
The MGL ASI-1 is digital up to 250mph. Easy to read. Can be switched to km/h or knots. Programmable bugs, log, timer and trip counter. So you can have your cake and eat it to:)! Goes for about $280.

Dave S
01-12-2014, 11:20 AM
Ken,

I have a second hand Falcon ASI that goes to 160 MPH.....Something like $45 at Wentworth and works fine.

This one is calibrated in MPH only....The philosophical discussion about MPH vs Knots is just that....entirely philosophical.....as a practical matter either works.

I totally agree with your comment that having more spread between the numbers is good.....I also think the simplicity of a single scale, rather than both MPH & Knots is good...both on the same dial creates an unnecessarily busy display IMHO.

Personally I like the wider spacing of the numbers and single scale....I'd rather be looking out the window than squinting at the ASI any longer than necessary anyway:D.

Sincerely,

Dave S
KF7 TRigear
912ULS Warp Drive

ken nougaret
01-12-2014, 11:28 AM
My thoughts exactly Dave.
Thanks for the info danzer1, sounds like a good unit but going for the traditional 6 pack look of dial gauges. Old fashion i guess.
Ken

SkyPirate
01-12-2014, 12:13 PM
I have the traditional guages as well, 1 is a quad for egt/cht, i dont have a water temp guage yet, but its on the list, i've heard that some have had problems with the quad guages,
So im building a new panel and havent commited yet to changing out the quad, i have a 2.25 tach that is getting replaced with a 3.25, and im still deciding on which com,i like the 2.25 radios size and weight,..sticking with the ifly gps, hopefully i will have a lighter panel when done, the builder used 1/8" aluminum im using .050

Danzer1
01-12-2014, 12:17 PM
I understand Ken - that's why we do what we do - we can each choose what we like.


This one is calibrated in MPH only....The philosophical discussion about MPH vs Knots is just that....entirely philosophical.....as a practical matter either works.

One could argue, it is not entirely philosophical, if one deals with ATC on any regular basis. I am given knots all the time and it's just one less conversion I have to make when I can see them both or just flip flop to either one.

Greg - Go Broncos!

ken nougaret
01-12-2014, 12:21 PM
Chase,
My 6 pack is 3 1/8 but i just bought a 2 1/4 tach. I hope its big enough to read.

HighWing
01-12-2014, 08:58 PM
I like MPH. I would say the vast majority of Kitfox owners talk in MPH. You might want to search other threads talking about cruise and stall. Can't rememeber when I last talked to ATC, but that is just me and maybe a couple of others.

The 2-1/4" tach. Not a problem. I find it much easier to see the relative pisition of a needle on a round gauge - even a relatively small round gauge than read the much smaller numbers on a digital readout.

Regarding the Quad Gauge. I liked it on my first Model IV and have another one on the new one. My understanding is that the new senders are more robust and reliable - also more expensive.

ken nougaret
01-13-2014, 08:45 AM
good point about atc. I talk to Orlando atc about 2 times a month. the only thing they've ever said to me concerning speed is: "keep your airspeed up". I tell them: "i'm giving her all I've got captain". i'm only flying a Cherokee. wait till they see a fox coming in.

Danzer1
01-13-2014, 09:10 AM
even a relatively small round gauge than read the much smaller numbers on a digital readout.Not to be argumentative, but here is a to scale comparison for reference both 2-1/4":


6030

Quick glance to exact number. Quick flip flop to knots.

Dave S
01-13-2014, 09:56 AM
Ken & Lowell,

Good points on the ATC question......this is more about operations than instruments but they are certainly connected.

Very familiar with the instruction to "Keep the speed up"....I get that more with the kitfox than I did with the Arrow ;)....

I have also found that tower controllers appreciate a pilot of a kitfox category airplane voluntarily stating they will "maintain cruise speed descent to the runway and land on the last 1/4 of the runway...a pretty easy task when a Kitfox is confronted with a 12,000' runway when things are tight. :)

Sincerely,

Dave S

HighWing
01-13-2014, 11:55 AM
Not to be argumentative, but...

I agree that one can become accustomed to a digital readout, but studies have clearly shown that a needle in reference to a constant background is intuitively understood at a glance. That is why in autos with analog gauges, the normal readings are usually with the needle centered virtically (or horizontally), typically with no numbers. Deviation from normal is understood even by the kids in the back seat. In our gauges, add in the colored speed range arcs and numbers no longer have significance because with a little practice, a quicker glance shows exactly where you are in respect to critical airspeeds and this will apply regardless of who's airplane you are flying. Maybe a better example of the intuitive read of a needle is the VSI. Much easier to understand than a number with a + or - preceeding it.

I can see going digital if you have a fuel flow system that calculates fuel burn and hours left in the tank, but for me the pilot, I prefer something more intuitive than a number that needs my brain to interpret.

SkySteve
01-13-2014, 12:48 PM
land on the last 1/4 of the runway...a pretty easy task when a Kitfox is confronted with a 12,000' runway when things are tight.

1/4 of 12,000'? That's 3,000' right. We can all land several times in that distance. :D:D;)

I just tell them I'll land long and exit at the first taxiway. They like it.