i think i need explain for Janes.Ha ha.
Janes classify under main uses.Pegasus is bascially a towed
gun.
SP is just for shoot and scoot or the towing is not
feasible.
Eg urban areas,narrow terrain etc.
M 777 is a Pure towed
gun.It must be moved by external power.
So,its firing sys to receive firing order is also supported by
external power!!
If u watch the Canadian force video,u can imagine:
While few guys is emplace the gun,one or two have to switch
on small generator for the firing order comm equipment
and connect wire to the gun.I find one guy also instal the
sight!!
So,when u displace,u have to do all the above again!!

Dunt tell me the isolated sight(at your left) will be in this
position
when the gun is travelling!!
So,u have to take the sight down when u displace
and put it back when u emplace!!
@@@@@@@@@@
"Top traverse is 400 mils
(23°) left and right."@
U have to do your displacement and emplacement if u receive
order outside this range!!Good luck!!That mean,call the truck
driver
etc lah....Just to shift few feet!!So again,where is the
power!!
May the Force be with u!!
@@@@@@@@@@
Compare with Pegasus sight which can stand 90 G,
(at top right hand corner of a photo i posted earlier)!
I dunt think u need to fix and put it down so troublesome!!
no.1 below---Pegasus sight can stand 90 G!!
no 2 below--M 777 sight.U have to take it down!!
no 3 and 4,Pegasus as shown in Airshow,Singapore.




http://kr.blog.yahoo.com/shinecommerce/archive/2007/12/16?m=lc
ref
@http://www.janes.com/articles/Janes-Armour-and-Artillery/BAE-Systems-Land-Systems-155-mm-Lightweight-Howitzer-M777-United-Kingdom.html