Altimeter setting question

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07-01-2011 | 06:34 PM

snippercr

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Does NOT get weekends off

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From: ERJ - 145

Altimeter setting question

So I am a little ashamed that I have to ask this but here goes anyways.

I for the life of me cannot remember how to calculate this. Let's say we are cruising around at FL290 and we get a descent down to 5,000 feet. Local altimeter is 30.50 and we forget to set it (it is left at 29.92). We level off at 5,000 feet, what is our TRUE altitude? To me this seems like a low (29.92) to high (30.50) so we would be 580 feet higher than we should be. That is if we reset our altimeter correctly, it would show 5,580 feet. Am I doing this bass ackwards?

Thanks,
Ashamed CFI

07-01-2011 | 11:11 PM

Mr Immlemann

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From: Im workin on it...

Seems fine to me. 1 inch hg=1000. dif between 29.92 and 30.50=580ft. Your going from 29.92 to 30.50 because your forgot to reset which means an increase in your indicated alt. So 5000ft at 29.92 will equal 5580 when you increase your alt setting to 30.50. Unless I'm wrong too

07-01-2011 | 11:28 PM

Bellanca

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From: CFI/II/MEI

You should be right, there's the "from a high to a low, look out below" saying and you're going the opposite direction so you're right that you will be high.

07-01-2011 | 11:55 PM

Singlecoil

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From: Supine

You are doing the conversion correctly, but 5580 is your indicated altitude. True altitude is indicated altitude corrected for non-standard temperature.

07-06-2011 | 08:50 AM

KLM pilot

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From: B747 FO

Easiest way I remember, dial the scale up, the altimeter goes up, dial the scale down, the altimeter goes down. So if you were cruising with standard and the local altimeter is, say, 2980, when you dial that in the altimeter goes down. If you forget to do that, you would actually be flying lower than indicated! Hope that helps