Pushing the Speed of Light (not too hard, but pushing it...)

If in normal space, you will almost certainly be within a star system so the particle density would be much higher than that of the ISM. And even more so in hyperspace.

I cannot remember seeing any figures for a buckler's size or distance from the ship, but in order to be useful in combat it would have to be at least one of: very close, quite large or movable. Even calling it a "buckler" implies it is movable. Any of these would alleviate the potential maneuvering problems.

A bigger problem would be that the buckler is a combat system, like the sidewalls, and so would only be designed for relatively short-duration operation.

It would be easier just to beef up the radiation shielding, possibly even with a specialised low-power-but-long-duration version of the buckler. The arbitrary and universal constant value of the maximum speed for all warships is really a bit of handwavium. In reality there would likely be some variation between ship designs, with heavier ships capable of higher maximum speeds due to heavier shielding. Similarly, the maximum achievable speed should vary from system to system and especially at different distances from the star due to varying particle densities. But that is part of the canon.

Rugdumph wrote:I cannot remember seeing any figures for a buckler's size or distance from the ship, but in order to be useful in combat it would have to be at least one of: very close, quite large or movable. Even calling it a "buckler" implies it is movable. Any of these would alleviate the potential maneuvering problems.

The only place I recall its size being mentioned in is Shadows of Saganami when we're first introduced to the concept; on Hexapuma. "It was a much smaller, circular shield, its diameter less than twice the ship's extreme beam." [SoS: Ch 24]

We're not told it's standoff distance but my assumption has been that it needs to be at the same distance from the hull as a normal sidewall (10km) in order to be effective.

MuonNeutrino wrote:
The real problem with the buckler acting as a particle shield at speeds where normal particle shields would fail is that it only will work as long as the ship's orientation *exactly* matches its vector - as soon as the ship rotates to accelerate in a different direction than the one it's currently moving, the buckler swings out of line with the flow and all those particles start smashing right through your regular particle shielding. Given that you can't maneuver at all (or even slow down!) without changing heading, it would be impossible in a practical sense to actually safely use a buckler as a shield even if it might be theoretically possible. (Barring, as munroburton mentions, the possibility of making a downwards hyper translation to bleed off speed, but even then the inability to do anything other than go in straight lines would be crippling.)

I remember having some extensive discussions here, a few years ago after the buckler wall was introduced, about exactly these issues.

There's is one, potential, very awkward way to slow down without making a downward translation - but it relies on the switch from buckler to full wall being seamless. If it is you could switch to full bow wall, then use thrusters to pitch or yaw enough to catch the particles on your wedge or sidewall. Drop the bow wall, raise a full stern wall; continue your maneuver until the full 180 has been accomplished then shrink the stern wall into a stern buckler and begin decelerating.
But you're maneuvering options are still very limited; and you certainly couldn't pull that trick in a grav wave.

(My personal suspicion is that a normal bow wave generator can't generate a bow wall in a 'wave in the first place. But even if I'm wrong you don't have the rest of what you'd need to try this trick - full bow/stern walls, wedge or sidewalls)

However my bet is that you can't use a buckler to exceed the normal speed limits.