July 4, 2014 at 5:53 pm
Possibly a bit esoteric, however, I have produced a new video with demonstrations of the manual German VDM Propeller pitch control system as fitted to many WW2 german aircraft. It is not perfect and I haven’t gone into excessive detail however I feel it does answer a few common questions and mis-understandings surrounding the prop pitch control on aircraft such as the 109. My next video will cover the more complicated automatic system with demonstrations of the working system too!
cheers
Matt
By: Augsburgeagle - 6th July 2014 at 19:54
No Problem Peter,
Got to sort out the auto video now, not quite as simple a task! I will produce videos for all the major systems and engine systems, if anyone has a DB605 or DB601 they would mind me filming for illustration purposes, let me know 😉
cheers
Matt
By: Peter D Evans - 6th July 2014 at 10:58
Thanks for that Matt… I’ll be adding the link to the LEMB too 😉
Cheers
Pete
By: Augsburgeagle - 6th July 2014 at 10:34
I’m not sure as to why the clock style display was chosen, it probably explains it in one of my references so I’ll have a wade through.
My only guess is that because the system is universal; when setting the system up in an aircraft you alter the end points for the EVG depending on the aircraft, for example the 109G’s are from about 1230 to 0450-0430, however in an E with 601A it’s 1230 to 0250-0230, with a clock with no face markings you can display both these sets of information on the same instrument, I don’t think a linear display this information as clearly. The other thing is that the pitch required to maintain a given engine RPM depends upon the aircrafts speed (true airspeed-TAS) and so the pitch needed at 200kph to maintain 2600rpm (for example) would not be the same as that required at 400kph, I think the unmarked clock face reflects the dynamic nature of the relationship between required prop pitch and TAS without being confusing.
As some sort of compact display instrument was required that had to be universal non confusing and unambiguous the clock style seemed a good choice. My guesses!
Matt
By: Creaking Door - 5th July 2014 at 23:18
Excellent explanation of the system…
…but that ‘clock’ propeller-pitch instrument has got to be about the worst instrument ever fitted to an aircraft.
Is there any reason why it was arranged that way…..other than using-up surplus clock components?
By: Versuch - 5th July 2014 at 09:47
Excellent Matt…looking forward to your next project.
Kind Regards Mike
By: Avro Avian - 5th July 2014 at 01:08
Good explanation Matt. Thanks! 🙂