diff --git a/src/battle/fighters.c b/src/battle/fighters.c
index a331a8e..d0806f7 100644
--- a/src/battle/fighters.c
+++ b/src/battle/fighters.c
@@ -355,11 +355,12 @@ void applyFighterThrust(void)
 	self->dy += -cos(TO_RAIDANS(self->angle)) * 0.1;
 	self->thrust = sqrt((self->dx * self->dx) + (self->dy * self->dy));
 	
-	if (self->thrust > self->speed * self->speed)
+	while (self->thrust > self->speed * self->speed)
 	{
 		v = (self->speed / sqrt(self->thrust));
 		self->dx = v * self->dx;
 		self->dy = v * self->dy;
+		self->thrust = sqrt((self->dx * self->dx) + (self->dy * self->dy));
 	}
 }
 
diff --git a/src/battle/hud.c b/src/battle/hud.c
index 7e448d6..897af29 100644
--- a/src/battle/hud.c
+++ b/src/battle/hud.c
@@ -30,7 +30,7 @@ static void drawDistancesInfo(void);
 static void drawHudMessages(void);
 static void drawPlayerSelect(void);
 static void drawAbilityBars(void);
-static void drawBoostECMBar(int x, int y, int r, int g, int b, int available);
+static void drawBoostECMBar(int current, int max, int x, int y, int r, int g, int b);
 
 static HudMessage hudMessageHead;
 static HudMessage *hudMessageTail;
@@ -216,15 +216,18 @@ static void drawHealthShieldBar(int current, int max, int x, int y, int r, int g
 
 static void drawAbilityBars(void)
 {
-	drawBoostECMBar(10, 50, 128, 128, 255, battle.boostTimer == 0);
+	drawBoostECMBar(battle.boostTimer, BOOST_RECHARGE_TIME, 10, 50, 128, 128, 255);
 	
-	drawBoostECMBar(160, 50, 255, 128, 0, battle.ecmTimer == 0);
+	drawBoostECMBar(battle.ecmTimer, ECM_RECHARGE_TIME, 160, 50, 255, 128, 0);
 }
 
-static void drawBoostECMBar(int x, int y, int r, int g, int b, int available)
+static void drawBoostECMBar(int current, int max, int x, int y, int r, int g, int b)
 {
 	SDL_Rect rect;
 	
+	float percent = current;
+	percent /= max;
+	
 	rect.x = x;
 	rect.y = y;
 	rect.w = 100;
@@ -236,16 +239,22 @@ static void drawBoostECMBar(int x, int y, int r, int g, int b, int available)
 	SDL_SetRenderDrawColor(app.renderer, 255, 255, 255, 255);
 	SDL_RenderDrawRect(app.renderer, &rect);
 	
-	if (available)
+	rect.x += 2;
+	rect.y += 2;
+	rect.w -= 4;
+	rect.h -= 4;
+	
+	rect.w *= percent;
+	
+	if (current < max)
 	{
-		rect.x += 2;
-		rect.y += 2;
-		rect.w -= 4;
-		rect.h -= 4;
-		
-		SDL_SetRenderDrawColor(app.renderer, r, g, b, 255);
-		SDL_RenderFillRect(app.renderer, &rect);
+		r /= 2;
+		g /= 2;
+		b /= 2;
 	}
+	
+	SDL_SetRenderDrawColor(app.renderer, r, g, b, 255);
+	SDL_RenderFillRect(app.renderer, &rect);
 }
 
 static void drawWeaponInfo(void)
diff --git a/src/battle/player.c b/src/battle/player.c
index adf9f2d..326a387 100644
--- a/src/battle/player.c
+++ b/src/battle/player.c
@@ -59,16 +59,16 @@ void initPlayer(void)
 	
 	player->action = NULL;
 	
-	battle.boostTimer = 0;
-	battle.ecmTimer = 0;
+	battle.boostTimer = BOOST_RECHARGE_TIME;
+	battle.ecmTimer = ECM_RECHARGE_TIME;
 }
 
 void doPlayer(void)
 {
-	battle.boostTimer = MAX(battle.boostTimer - 1, 0);
-	battle.ecmTimer = MAX(battle.ecmTimer - 1, 0);
+	battle.boostTimer = MIN(battle.boostTimer + 1, BOOST_RECHARGE_TIME);
+	battle.ecmTimer = MIN(battle.ecmTimer + 1, ECM_RECHARGE_TIME);
 	
-	if (battle.boostTimer == BOOST_FINISHED_TIME)
+	if (battle.boostTimer == (int)BOOST_FINISHED_TIME)
 	{
 		applyFighterThrust();
 	}
@@ -89,7 +89,7 @@ void doPlayer(void)
 				player->angle += 4;
 			}
 			
-			if (app.keyboard[SDL_SCANCODE_UP] && battle.boostTimer < BOOST_FINISHED_TIME)
+			if (app.keyboard[SDL_SCANCODE_UP] && battle.boostTimer > BOOST_FINISHED_TIME)
 			{
 				applyFighterThrust();
 			}
@@ -132,12 +132,14 @@ void doPlayer(void)
 				app.keyboard[SDLK_t] = 0;
 			}
 			
-			if (app.keyboard[SDL_SCANCODE_SPACE] && !battle.boostTimer)
+			if (app.keyboard[SDL_SCANCODE_SPACE] && battle.boostTimer == BOOST_RECHARGE_TIME)
 			{
+				playSound(SND_BOOST);
+				
 				activateBoost();
 			}
 			
-			if (app.keyboard[SDL_SCANCODE_E] && !battle.ecmTimer)
+			if (app.keyboard[SDL_SCANCODE_E] && battle.ecmTimer == ECM_RECHARGE_TIME)
 			{
 				activateECM();
 			}
@@ -242,12 +244,12 @@ static void activateBoost(void)
 	self->dy += -cos(TO_RAIDANS(self->angle)) * 10;
 	self->thrust = sqrt((self->dx * self->dx) + (self->dy * self->dy));
 	
-	battle.boostTimer = BOOST_RECHARGE_TIME;
+	battle.boostTimer = 0;
 }
 
 static void activateECM(void)
 {
-	battle.ecmTimer = ECM_RECHARGE_TIME;
+	battle.ecmTimer = 0;
 }
 
 static void switchGuns(void)
diff --git a/src/battle/player.h b/src/battle/player.h
index b4454a3..432165c 100644
--- a/src/battle/player.h
+++ b/src/battle/player.h
@@ -32,6 +32,7 @@ extern void applyFighterBrakes(void);
 extern int getDistance(int x1, int y1, int x2, int y2);
 extern void addHudMessage(SDL_Color c, char *format, ...);
 extern int mod(int n, int x);
+extern void playSound(int id);
 extern void failMission(void);
 
 extern App app;
diff --git a/src/defs.h b/src/defs.h
index 3144e3b..ba56fc5 100644
--- a/src/defs.h
+++ b/src/defs.h
@@ -76,7 +76,7 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 
 /* player abilities */
 #define BOOST_RECHARGE_TIME 	(FPS * 5)
-#define BOOST_FINISHED_TIME 	(BOOST_RECHARGE_TIME - FPS * 0.5)
+#define BOOST_FINISHED_TIME 	(FPS * 0.75)
 #define ECM_RECHARGE_TIME		(FPS * 5)
 
 enum
@@ -153,6 +153,7 @@ enum
 	SND_EXPLOSION_3,
 	SND_EXPLOSION_4,
 	SND_MISSILE,
+	SND_BOOST,
 	SND_GUI_CLICK,
 	SND_GUI_SELECT,
 	SND_GUI_CLOSE,