Question on CSP

[piperboy84]

Does the governor on a CSP have the same stand alone range of pitch changing authority as using the prop handle manually adjusted to its extremes does , what I mean by this is if the pitch range of a CSP is say 12 degrees thru 26 degrees, once the rpm is set on the prop handle and left to the governor to maintain that RPM is the governor capable of utilizing the full 12 thru 26 degree range in trying to maintain a constant rpm.

I understand this question has no application in the real world as you would not fly those underspeed or overspeed extremes , my questions more just about governor capabilities and design

[garrya100]

The governor will use all the available pitch to keep the prop at the RPM you have set. Once it runs out of pitch control it will slow or speed up in the same manner a fixed pitch prop will.

[1Charlie]

From how I understand it, when you adjust the propellor lever you're not adjusting the pitch of the blades. You're only adjusting what RPM the governor will limit at. The governor will then adjust the pitch through 12-26 degrees in order to maintain that RPM. I guess it often sits at its full fine limit (12 degrees, when in descent or taxying) but would seldom reach full coarse.

I apologise if that's not what you're asking.

[piperboy84]

I guess it often sits at its full fine limit (12 degrees, when in descent or taxying) but would seldom reach full coarse.

I apologise if that's not what you're asking.

That is what I am asking, however a bit of subject drift to clarify another prop issue you mentioned, would the prop not go to course on descent as opposed to fine (12 degrees) in your example above?

[BackPacker]

That would depend on your rate of descent. In a normal descent, where you retard the throttle but keep the IAS constant, to obtain a ROD of about 500 ft/min, nothing special is going to happen. The governor will simply use the available blade pitch range to maintain the set RPM.

But if you do a full power vertical descent, I can assure you that the coarse pitch stops will be reached very quickly indeed. This will result in the engine overspeeding, as the governor doesn't have enough blade pitch authority to keep the RPM in check.