PURPOSE of Pitot Tubes on bombers?

Re:PURPOSE of Pitot Tubes on bombers? (AlanStarcher)

Fri, 11 May 2012 17:31:00 GMT

What do you know? Here's another photo, and someone DID hang their jacket on it!

Or maybe it's a scarf.

Re:PURPOSE of Pitot Tubes on bombers? (AlanStarcher)

Fri, 11 May 2012 17:26:02 GMT

Al Blue has a better photo in his book, The B-24 Liberator on page 54 -- that's where I stole the idea to look through my photos to find this one. I had to look it up to see what we were talking about -- I first assumed that the small tab on the top of the nose, at the front of the bomb (mission) markings close to where the old pitot would have been mounted, was the flush pitot.

The old style on the B-17 was called a D-1 or "mast-type" pitot (installed in pairs), and the new style a single G-2 mounted on the lower port side of the Lib. I wonder -- why was it called a "flush" pitot? It seems that you could hang your jacket on it, and I bet it would leave a mark if you carelessly walked into it -- especially hazardous since it is mounted so low. Eh?

-- Alan

Re:PURPOSE of Pitot Tubes on bombers? (WillowRun)

Fri, 11 May 2012 07:33:31 GMT

Alan, Great, clear pic of pitot on the "Witchcraft" showing its position on later Lib variants as I mentioned in my post #4 ("In later production versions, late "J"s along with all "L"s and "M"s at FO WR, the G-2 flush pitot became part of the assembly process." this also occurred at other facilities as well.) In many photos, it is difficult to see the flush pitot, but this shot is extremely clear. Thanks for sharing for the Membership!

Re:PURPOSE of Pitot Tubes on bombers? (AlanStarcher)

Thu, 10 May 2012 19:47:18 GMT

Couldn't leave out the B-24J. Pitot, pitot -- where is the pitot?

Hints: serial 44-44052, Fort Worth, TX-built. She's a B-24J-85-CF.

-- Alan

Re:PURPOSE of Pitot Tubes on bombers? (AlanStarcher)

Thu, 10 May 2012 19:44:34 GMT

The pitot is visible just above the hand of the nose art character. This is the Collings Foundation B-17G, serial 44-83575.

-- Alan

Re:PURPOSE of Pitot Tubes on bombers? (WillowRun)

Thu, 10 May 2012 10:26:49 GMT

drummerboy
What are Pitot Tubes located on the nose on the bomber?
Were they used to measure the air speed of the aircraft ?
Were they retained on the B-17G or were they relocated or removed ?

Ernie, All of these posts give excellent information on your query. In post #2, Dennis, also added some great links for general reading when you have some time. To add a bit to Jim Peters' post, similarally on the B-24s the forward positioning was much the same although the vertical location varied with the variant changes. They also had self-contained electrical heating elements to prevent internal ice formation. On the first Lib (XB-24, 39-556) the pitot tubes were located on the outer wings but were later relocated on the forward fuselage (XB-24Bs). In later production versions, late "J"s along with all "L"s and "M"s at FO WR, the G-2 flush pitot became part of the assembly process.

Re:PURPOSE of Pitot Tubes on bombers? (jpeters140)

Wed, 09 May 2012 21:33:38 GMT

As additional information...when an aircraft is in the Experimental developement, test pitot tube is usually some 4-6 ft forward of the nose...in order to get an accurate reading in undisturbed air....the foremost point of the end of test pitot tube becomes fuselage Station 0....and as the nose of the aircraft is the aforementioned 4-6 ft aft...that fuselage point then becomes fuselage Station 4 or 6 (or whatever distance), with all subsequent stations aft measured in inches.

During the testing, several other locations are determined to be in undisturbed air, and the permanent pitot tubes are then incorporated into the aircraft.

This is why all aircraft usually have the extreme nose of the aircraft, as other than fuselage Station 0, depending on the length of the test pitot probe.

Jim ( learned when I was a QC Inspector at Boeing).

Re:PURPOSE of Pitot Tubes on bombers? (Anthony J. Mireles)

Wed, 09 May 2012 16:27:35 GMT

Pitot tubes on all aircraft run the altimeter, vertical speed indicator and airspeed indicator.
On B-17G, pitot runs cockpit and bombardier instruments.
The bombardier controls has its own airspeed and altimeter.

Re:PURPOSE of Pitot Tubes on bombers? (dennis_burke)

Wed, 09 May 2012 16:03:26 GMT

Lots out there on the internet on Pitot tubes, basic airspeed measuring device on almost all aircraft.

http://en.wikipedia.org/wiki/Pitot_tube
http://www.engineeringtoolbox.com/pitot-tubes-d_612.html
http://www.scientificamerican.com/article.cfm?id=what-is-a-pitot-tube
http://en.wikipedia.org/wiki/Pitot-static_system
http://gcmd.nasa.gov/KeywordSearch/Supplementals.do?Portal=wdc&KeywordPath=Instruments&EntryId=PITOT-STATIC%20SYSTEM&MetadataType=3&lbnode=mdlb2
Not sure where they were on the B-17G but this sites seems to be a transcription of B-17G manuals.
http://www.airpages.ru/eng/mn/b17_07.shtml
Quote: A single pitot static mast, placed just below the body center line aft of the chin turret and above the forward entrance hatch, replaces the two pitot static masts with which the B-17F is equipped.

Cheers from Ireland
Dennis

PURPOSE of Pitot Tubes on bombers? (drummerboy)

Wed, 09 May 2012 15:45:27 GMT

What are Pitot Tubes located on the nose on the bomber?
Were they used to measure the air speed of the aircraft ?
Were they retained on the B-17G or were they relocated or removed ?