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Why are traditional style cockpits with gauges called 'steam cockpits'? Do the instruments actually run on steam?

Lnafziger
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flyingfisch
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    The term is actually "steam gauges" - I've never heard anybody refer to a "steam cockpit". – egid Apr 26 '14 at 03:15
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    I think it's simply because glass dial gauges resemble steam pressure gauges (e.g. on a steam engine, turbine, whatever). Certainly no aviation instruments have ever run on steam that I'm aware of. – TypeIA Apr 26 '14 at 03:26
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    @dvnrrs well, there is steampunk, but they usually prefer airships ;-) – yankeekilo Apr 26 '14 at 15:10
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    I was a C130 Navigator and rode on them for about 25 years (the pilots drove me to work) and never really flew with a true glass cockpit, but....I never heard the gauges we used (and they had pointers/calibrated scale/and were round} referred to as "steam gauges" but reading the comments maybe I didn't pay it enough attention? Oh well, we always got to where we where going. –  Oct 07 '16 at 00:09
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    I don't know about the instruments, but the engine of at least one airplane ran on steam. – Mark Feb 24 '17 at 22:38
  • Well, some flight simulators probably run on Steam... – Vikki May 25 '20 at 21:19

2 Answers2

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Well, to answer your second question first: no. No aircraft instruments actually run on steam. There are lots of safety issues related to generating and using the steam on board an aircraft that are prohibitive.

As far as why they are called steam gauges, take a look at one and compare it to a traditional flight instrument:

Steam Gauge Airspeed Indicator

They are both round, both have a calibrated scale printed on them, and both have a needle which points at the current value. They actually look pretty similar!

Lnafziger
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    so is a car speedometer/tachometer also a steam gauge? – shortstheory Apr 26 '14 at 07:40
  • Heh, I always thought "steam gauges" referred to vacuum gyro-instruments (as they work the same way, only backwards, pulling air out rather than pushing steam in..) – falstro Apr 26 '14 at 07:46
  • @shortstheory I've never heard them called that, but aviation is a more technical field so maybe it arose from people who worked wih both, back in the early days. – Lnafziger Apr 26 '14 at 12:48
  • @falstro Well,the airspeed indicator, the altimeter, and the VSI are not vacuum powered but are called steam gauges! – Lnafziger Apr 26 '14 at 12:50
  • @Lnafziger Oh I'm sure you're right! I just thought it was interesting how much we just assume sometimes :) – falstro Apr 26 '14 at 13:14
  • @Lnafziger: They're called "vacuum gyro-instruments" because the instruments measure the outputs of a vacuum-powered gyro. In other words, the vacuum makes the gyro spin. The instruments that measure the gyro (attitude, heading) are not themselves directly measuring pressure, as opposed to the airspeed indicator and altimeter, which are examples of instrments that directly measure pressure (just like a steam gauge). – Gabe May 04 '14 at 17:58
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I never heard the term "steam gauge" until there were glass cockpits - but maybe that is just me. A "steam gauge airplane" is a mildly derogative term to indicate that the plane has instruments that are old fashioned, borderline obsolete. But they work just fine! I fly a steam gauge airplane.

Skip Miller
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    Live and learn, I guess. This question was the first time I've ever heard the term "steam cockpit." This is all making me feel really old. – Terry Apr 26 '14 at 14:46
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    @Terry I've never heard the term "steam cockpit" either, but "steam gauges" are a relatively common term now. – Lnafziger Apr 26 '14 at 18:18
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    Well, before glass cockpits all instruments were of the "steam gauge" type, so there was no need to have a name for them. – Jan Hudec Apr 28 '14 at 06:35
  • There would never have been a reason to call them "steam" gauges until the emergence of glass cockpits. As a term to distinguish between them, "steam" would certainly suggest an image of round gauges with moving mechanical pointers commonly seen on steam-powered equipment. "Glass" cockpit seems a funny term... "steam" gauges have glass faces on them, just like digital displays do. – Anthony X Jul 31 '15 at 01:10
  • Skip's experience in the emergence of the term matches mine, in terms of arising only when glass cockpits became more and more ubiquitous. It is indeed a (slightly) derogatory term but I am not sure who started it. Might be neat trivia to know. – KorvinStarmast Oct 07 '16 at 05:00
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    I just did a google books search on various combinations of "steam gauge" and airplane from 1930-1980 and got no hits, so I too suspect that the term wasn’t coined until the advent of glass cockpits. – JScarry Oct 07 '16 at 20:50
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    @KorvinStarmast Probably not the first occurrance but in 1993 the Pilot Vehicle Interface document from the FAA mentions 'Older cockpits contained numerous "steam gauge" style indicators.' http://bit.ly/2cXIbRq – JScarry Oct 07 '16 at 20:59