Originally Posted by
TangoAlphad
All the artificial horizon is doing is replicating the outside picture but just on a much smaller scale so think about flying visually...
High speed high power for straight and level is relatively low nose i.e. On the horizon. So what about slow flight? Less speed and less power you are going to require a more nose up attitude to maintain level flight so looking out the window you are going to see the nose sitting relatively higher to the horizon. This will be exactly mimicked on the artificial horizon. It is only showing you a scaled down version of what you see out the window and will not compensate etc to give you level flight by lining up the aircraft display onto the horizon.
On the 737 (only figures I know off the top of my head) it could be anywhere from 1-2 degrees nose up to 5-6 degrees nose up for level flight depending on speed and altitude. Similarly for descent on the approach we are typically nose slightly above the horizon while descending.
I am guessing you are still fairly early in training (PPL) and not onto formal IR training yet? This will all come in time and if that is correct you shouldn't really be doing too much flying on instruments as it is a specialised skill set to do accurately while not attracting all of your attention. Your instructor will be able to brief it better in person but for a light aircraft the VSI does have lag in it so I'd suggest initially setting the aircraft to a known attitude and make small corrections around that in the order of a degree or so. Your scan will be for example between aritificial horizon - altimeter (slight correction) - artificial horizon -altimeter (confirm correction worked or adjust) -- speed - artificial horizon - Direction Indicator - artificial horizon - altimeter repeat. The VSI in most light aircraft is just going to lag too much to be accurate enough for instrument flying as an initial level off but you certainly keep it in your scan for other areas of flight.
NB: You said towards the end about using the VSI to adjust attitude rather than the artificial horizon. If you are going to adjust the aircraft in pitch or roll or power you must be doing it by reference to the Artificial horizon and then cross check off the other primary instruments or you will get into a world of trouble my friend.
Thanks for the reply. This explanation was exactly what I was looking for, and makes a lot of sense. Yes I am fairly early on, we were flying like this today as the weather wasn't great, but I said I wouldn't mind giving the instrument flying a go. Just wanted to get some clarity on some thoughts I had after doing it.
Thanks again! Very Helpful.