On the TB20, if this is pumped up to the specified value, the nose rides quite high. A lot higher than I have had for most of the 19 years I have owned the plane 
Fairly obviously it must help with prop clearance, which is a good thing when on grass.
I also reckon that having any compression on the nose strut under steady state conditions is just wasting prop clearance.
Yes. Downsides are: less pleasant to taxy and more difficult to land main gear first.
Peter wrote:
I also reckon that having any compression on the nose strut under steady state conditions is just wasting prop clearance.
That’s an interesting point, and worthy of discussion. Other than the propeller clearance issue it depends on whether the design objective is a suspension system or an impact absorber. Road vehicle suspensions are typically typically set with static sag utilizing about 1/3 of total travel. That provides a smooth ride over potholes (downward travel) without bottoming out over large bumps (upward travel). I think many or most aircraft when set to the recommended oleo gas pressure would also end up in this range.
Conversely there are a few other aircraft that for example utilize a fully ‘topped out’ sealed gas strut for the nose wheel, with no static sag at all. Except for tire deflection they are solid as a rock until reaching a specified preload force – in the range of 300 lbs depending on type. These provide no suspension at all while taxiing, but do provide a longer stroke under landing impact.
Which is better overall I have no idea, but I suspect having a little static sag is no bad thing.
Nose gear servicing is critical in both Gas pressure and oil quantity.
If the gear is properly serviced it insures that the shock strut provides the correct rising spring rate. This spring rate is critical for the correct dis- engagement of the centring mechanism and the engagement of the nose wheel steering system.
On some types the main gear shock strut servicing also has an influence on what happens at the nose gear.
I had a closer look the other day and with the nose gear gas strut pumped up fully, the TB20 with a 3B prop has 30cm of prop clearance.
With the strut pumped up halfway (the normal way) you have 20cm.
That’s a big difference.
With the 2B prop you have about 3cm less clearance.
