diff --git a/boot/helicopter.ks b/boot/helicopter.ks
new file mode 100644
index 0000000..dcf26aa
--- /dev/null
+++ b/boot/helicopter.ks
@@ -0,0 +1,12 @@
+// helicopter bootstrapping sequence
+
+deletepath("/boot/helicopter").
+
+// Install software.
+compile "0:/helicopter/ui" to "1:/init".
+compile "0:/helicopter/hover" to "1:/hover".
+
+// Set OS to boot and restart.
+set core:bootfilename to "/init".
+
+reboot.
diff --git a/boot/helicopter_debug.ks b/boot/helicopter_debug.ks
new file mode 100644
index 0000000..329682a
--- /dev/null
+++ b/boot/helicopter_debug.ks
@@ -0,0 +1,5 @@
+copypath("0:/helicopter/ui", "1:/init").
+copypath("0:/helicopter/hover", "1:/hover").
+
+CORE:PART:GETMODULE("kOSProcessor"):DOEVENT("Open Terminal").
+run "1:/init".
diff --git a/boot/rocket.ks b/boot/rocket.ks
index e2f8fae..87c4740 100644
--- a/boot/rocket.ks
+++ b/boot/rocket.ks
@@ -8,8 +8,8 @@ deletepath("/boot/rocket").
 compile "0:/lib/navigation" to "1:/lib/navigation".
 compile "0:/lib/throttle" to "1:/lib/throttle".
 compile "0:/rocket/ui" to "1:/init".
-compile "0:/rocket/launch" to "1:/rocket/launch".
-copypath("0:/rocket/execnode", "1:/rocket/execnode"). // larger when compiled
+compile "0:/rocket/launch" to "1:/launch".
+copypath("0:/rocket/execnode", "1:/execnode").
 
 // Set OS to boot and restart.
 set core:bootfilename to "/init".
diff --git a/helicopter/hover.ks b/helicopter/hover.ks
index 50ba662..31cbbd3 100644
--- a/helicopter/hover.ks
+++ b/helicopter/hover.ks
@@ -1,17 +1,54 @@
 // This script assumes you have bound collective (aka deploy angle) to main throttle.
 
-SAS off.
-local pitchPID is PIDLoop(0.01, 0.01, 0.01).
-local rollPID is PIDLoop(0.01, 0.01, 0.01).
-local collectivePID is PIDLoop(0.01, 0.01, 0.01).
+// SAS off. // debug: re-enable when adjusting heading
+local pitchPID is PIDLoop(0.01, 0.001, 0.001, -45, 45).
+set pitchPID:SETPOINT to 0.
+local rollPID is PIDLoop(0.01, 0.001, 0.001, -70, 70).
+set rollPID:SETPOINT to 0.
+local collectivePID is PIDLoop(0.1, 0.1, 0.001, 0, 1).
+set collectivePID:SETPOINT to 0.
 
-local yaw is SHIP:FACING:
 
-until SHIP:VELOCITY:SURFACE:MAG < 0.01 {
+local vel is 0. lock vel to SHIP:BODY:UP * SHIP:VELOCITY:SURFACE.
+set vecDraw(V(0,0,0), vel):show to true. // debug
+
+local x is 0. lock x to SHIP:FACING:FOREVECTOR * SHIP:VELOCITY:SURFACE.
+local y is 0. lock y to (SHIP:UP:FOREVECTOR * SHIP:VELOCITY:SURFACE) / (SHIP:VELOCITY:SURFACE:MAG * cos(VectorAngle(SHIP:UP:FOREVECTOR, SHIP:VELOCITY:SURFACE))).
+local z is 0. lock z to SHIP:FACING:RIGHTVECTOR * SHIP:VELOCITY:SURFACE.
+local spd is 0. lock spd to SHIP:VELOCITY:SURFACE:MAG.
+
+local done is false.
+
+on AG9 {
+  set done to true.
+}
+
+until done {
+  // debug
+  // print x + " " + y + " " + z.
+  print "Vertical Speed = " + y.
+
+  local newPitch is pitchPID:Update(TIME:SECONDS, spd). // was x
+  local newRoll is rollPid:Update(TIME:SECONDS, spd). // was z
+  local newThrot is collectivePID:Update(TIME:SECONDS, y). // was y
+
+  // debug
+  print "Yaw = " + mod(360 - SHIP:BEARING, 360).
+  print "Pitch = " + newPitch.
+  print "Roll = " + newRoll.
+  print "Throt = " + newThrot.
+  print "Spd = " + spd.
   
-
-  LOCK throttle to 
+  set SHIP:CONTROL:PILOTMAINTHROTTLE to newThrot.
+  // lock STEERING to Heading(
+  //   mod(360 - SHIP:BEARING, 360),
+  //   newPitch,
+  //   newRoll
+  //   ).
+  wait 0.001.
 }
 
 // Because helicopters can hover stably, once we achieve a hover we should be able to turn SAS on and call it good.
+unlock STEERING.
 SAS on.
+print "Hover operation canceled. Returning control.".
diff --git a/helicopter/ui.ks b/helicopter/ui.ks
new file mode 100644
index 0000000..91b714e
--- /dev/null
+++ b/helicopter/ui.ks
@@ -0,0 +1,16 @@
+// Main UI.
+local interface is gui(250, 300).
+set interface:X to 200.
+set interface:Y to 700.
+
+// Main menu elements in here.
+local y is interface:AddVLayout().
+local x is y:AddHLayout().
+
+set x:AddButton("HOVER"):onClick to {
+  run "hover".
+}.
+
+interface:show().
+
+wait until false.
diff --git a/rocket/launch.ks b/rocket/launch.ks
index 89f6b93..5221f64 100644
--- a/rocket/launch.ks
+++ b/rocket/launch.ks
@@ -61,7 +61,7 @@ wait 0.001. // make sure these control updates get applied
 
 print "Target apoapsis acquired. Creating maneuver node.".
 add CreateCircularizationNode().
-runpath("/rocket/execnode").
+runpath("/execnode").
 print "Orbit acquired. Releasing controls. Good luck, Kerman.".
 unlock THROTTLE.
 unlock STEERING.
diff --git a/rocket/ui.ks b/rocket/ui.ks
index 0a0d91a..b1c93ea 100644
--- a/rocket/ui.ks
+++ b/rocket/ui.ks
@@ -8,7 +8,7 @@ function launchButtonPressed {
   local oldStopTime is STEERINGMANAGER:MAXSTOPPINGTIME.
   set STEERINGMANAGER:MAXSTOPPINGTIME to maxStopTime:TEXT:ToNumber().
 
-  run "/rocket/launch"(
+  run "/launch"(
     targetApo:TEXT:ToNumber(),
     gravTurnStart:TEXT:ToNumber(),
     gravPitch:TEXT:ToNumber(),
@@ -51,7 +51,7 @@ set x:AddButton("LNCH"):onClick to {
     stk:ShowOnly(launchmenu).
 }.
 set x:AddButton("NODE"):onClick to {
-    run "/rocket/execnode".
+    run "/execnode".
 }.
 
 local stk is interface:AddStack().