Talk:Indicated airspeed

Latest comment: 9 months ago by Markrkrebs in topic The equation is (was) wrong

Does IAS change with Temperature? For example, if my IAS is 100 knots when it's 15 C outside should it change if the outside air temperature is 35 C? Maybe this question should be answered in the article.

Isn't the reason that Vne decreases with altitude because the critical mach number, which is a function of temperature, and thus a function of altitude, occurs at a lower IAS with increasing altitude? Otherwise, as was said in the main article, the aircraft will perform (absent mach effects) the same at the same IAS regardless of the TAS - so Vne (absent mach effects) would be at the same IAS regardless of altitude. —Preceding unsigned comment added by 71.28.207.58 (talk) 16:12, 20 August 2008 (UTC)Reply

Merge with File:Airspeed edit

It is suggested that this article be merged on redirected to the article Airspeed. The File:Airspeed discusses Indicated Airspeed well than this one...Freshymail-user_talk:fngosa--the-knowledge-defender —Preceding undated comment added 14:12, 31 August 2009 (UTC).Reply

What are IAS and KIAS? edit

This article is a stub. I did not know what IAS or KIAS was before reading this article and I still did not know what IAS or KIAS was after reading this article. I do not care if there is a lot of technical garbage in the article as long as the subject is defined or explained in layman's speak somewhere in the article. Someone please rewrite this for non pilots. here is a link to a site where I actually found out what KIAS was: http://stoenworks.com/Tutorials/Understanding%20airspeed.html (12.236.113.46 (talk) 18:35, 29 March 2011 (UTC))Reply

I'm sorry to see you didn't find what you were looking for on Wikipedia. The acronym IAS is explained in the first sentence of our article Indicated airspeed. KIAS is explained in the third sentence of our article. Dolphin (t) 21:49, 29 March 2011 (UTC)Reply

Wrong impressions, poor understamding edit

This article creates wrong impressions and betrays poor understanding IMO. Difficult to fix. Needs a bit of a re-write. The IAS is merely what the ASI says! That IAS->CAS is a monotonic function allows V-speeds to be specified as Indicated. That is useful because the pilot gets a reliable indicator of the stall speed, but the indicated stall speed at the start of the white region on the ASI is nothing like the calibrated stall speed or the true stall speed. E.g. in my Cessna 172 indicated airspeeds are well over 10 knots slower than calibrated airspeeds at Vs. Paul Beardsell (talk) 19:40, 16 May 2012 (UTC)Reply

Aircraft designers take great care to find a position for the static ports where position error will be a minimum in the cruise regime to minimise error in indicated altitude during cruise. Civil airworthiness standards prescribe a minimum acceptable error at speeds above 1.3 Vs but any amount of error is acceptable at slower speeds. A consequence of all this is that, for many aircraft designs, the position error near the stall is large. Dolphin (t) 03:42, 17 May 2012 (UTC)Reply

I understand what you write and agree with much of it. You merely pick at the edges of my argument. My central point stands. The IAS is what the ASI says. In my Cessna 172 the aircraft will (at 1g) stall at MAUW when the speed decays past the bottom of the white arc. But the IAS is far far lower than the TAS. You would never guess that from what the article did say. I have improved the article. It needs more work. Please improve the article. Paul Beardsell (talk) 22:24, 17 May 2012 (UTC)Reply

The equation is (was) wrong edit

dP ~ 1/2 * rho(0)*Vi^2 == 1/2*rho*Vtas^2 When you solve for Vias, the standard sea level density (not the local density) is in the denominator. As written, the equation does not subscript the density, leaving the impression it's the local value.Markrkrebs (talk) 12:50, 9 July 2023 (UTC)Reply

(I have presumed to fix it, just now. Please have a look. mrk) Markrkrebs (talk) 12:57, 9 July 2023 (UTC)Reply