[Milsurplus] Norden & the Autopilot

[Mahlon Haunschild]

And the bombardier's portion of the Pilot Direction Indicator (PDI) you 
can also see in the picture at:

http://aafradio.org/NASM/Bombardiers_Station.htm.

The round thingie with the tan-colored bar in the middle of it on top of the stabilizer is the PDI "transmitter", it's nothing more than a wirewound pot (The tan part) and a brush (the thing that looks like a pointer).  The brush is connected to the sighthead azimuth pivot; therefore, when the sighthead pivots to sight on an target in azimuth, the PDI moves also.  When the bombsight clutch is engaged (black thumb lever next to the PDI), the sighthead is mechanically connected to the directional gyro in the stabilizer.  As the gyro/sighthead turns, the brush turns also, making the above automatic (unless a change must be made; there are course knobs on the sighthead for that purpose).

The PDI in the cockpit is simply a meter connected to the PDI pot in the stabilizer.  Simple & effective.

When the autopilot clutch is engaged on the stabilizer (silver knob on top of the stabilizer) the autopilot is then connected to the directional gyro too.  Course changes from the bombardier then go to the autopilot as well.

So, the bombardier could steer the aircraft on the bomb run either through the PDI / pilot, or the autopilot.

More than you needed to know, I realize.  But I find the whole Norden 
bombsight/C-1 autopilot system at the close of WW II fascinating in its 
complexity, and yet it actually worked.  Sort of...

regards,

Mahlon - K4OQ

>------------------------------
>
>Message: 8
>Date: Sat, 18 Mar 2006 09:51:57 -0800
>From: "ROLYNN PRECHTL   K7DFW" <k7dfw at clatskanie.com>
>Subject: Re: [Milsurplus] Norden & the Autopilot
>To: <milsurplus at mailman.qth.net>
>Message-ID: <007701c64ab4$a6ec23a0$2c4c3ace at pygora>
>Content-Type: text/plain;	charset="iso-8859-1"
>
>
>  
>
>>And before that was done they had a thing called PDI which allowed the
>>    
>>
> <>bomb sight to give instructions to the human pilot.
> ===================================
>
> The MA-7A Bomb Nav system of the B-47E retained the PDI as part of the
> overall system.
>
>
> Rolynn
>
> Bomb/Nav flightline mechanic 32150E
> 40th Bomb Wing SAC
>
>