diff --git a/engine.lisp b/engine.lisp
index 6ad801e..c3fc53e 100644
--- a/engine.lisp
+++ b/engine.lisp
@@ -1,5 +1,6 @@
 (in-package #:flight-sim)
 
+
 (defclass engine-object (game-object)
  ((start-time :initarg :start-time :accessor start-time :initform 0)
   ;; time till fully active
@@ -10,6 +11,17 @@
 (defmethod activate ((object engine-object) start-time)
   (setf (start-time object) start-time))
 
+;; Engine Vertices &
+;; Engine colors
+;; array of color transforms for engine vertices
+;;   Each cell if an RGB array of transforms for the vertex
+;;     Each subcell is (Start-color Final-color Transform-time)
+;; 4 vertices
+;; each of 3 coords/colors
+;; each either:
+;;   Value
+;;   (start end time)
+
 (defclass engine-model (model)
   ((template-vertices :initarg :template-vertices :accessor template-vertices :initform nil)
    (template-colors :initarg :template-colors :accessor template-colors :initform nil)))
@@ -31,21 +43,40 @@
   (setf (vertices model) (generate-step-2d-array (template-vertices model) time))
   (setf (colors model) (generate-step-2d-array (template-colors model) time)))
 
+(defun make-thruster-vertices (start-model final-model duration)
+  (loop for i from 0 to (1- (length start-model)) collect
+       (let ((start (elt start-model i))
+	     (final (elt final-model i)))
+	 (loop for x from 0 to 2 collect
+	      ;(if (eql (elt start x) (elt final x))
+		;  x
+		  (list (elt start x) (elt final x) duration)))));)
 
 (defparameter *thruster-vertices* 
-  '((0.0 0.5 0.0) (-2.0 -0.5 0.0) (2.0 -0.5 0.0) 
-    ; z goes from 0 to 1 in 2 seconds
-    (0.0 0.0 (0 1.5 2))))
+  (make-thruster-vertices                                                                                                                          
+   '( (0.0 0.5 0.0) (-2.0 -0.5 0.0) (2.0 -0.5 0.0) (0.0 0.0 0.0))
+   '( (0.0 0.5 0.0) (-2.0 -0.5 0.0) (2.0 -0.5 0.0) (0.0 1.5 0.0))
+   2))
+;  '((0.0 0.5 0.0) (-2.0 -0.5 0.0) (2.0 -0.5 0.0) 
+;    ; z goes from 0 to 1 in 2 seconds
+;    (0.0 0.0 (0 1.5 2))))
+
+(defun make-thruster-colors (base-color-start base-color-final tip-color-start tip-color-final duration)
+  (append (loop for i from 1 to 3 collect 
+	     (loop for x from 0 to 2 collect
+		  (list (elt base-color-start x) (elt base-color-final x) duration)))
+	(loop for x from 0 to 2 collect
+	     (list (elt tip-color-start x) (elt tip-color-final x) duration))))
 
 (defparameter *thruster-colors*
-  '(((32 64 2) (32 132 2) (32 164 2))
-    ((32 64 2) (32 132 2) (32 164 2))
-    ((32 64 2) (32 132 2) (32 164 2))
-    ((0 255 2) (0 255 2) (64 255 2))))
+  (make-thruster-colors '(32 32 32) '(64 132 164) '(0 0 64) '(255 255 255) 2))
+;  '(((32 64 2) (32 132 2) (32 164 2))  ;; vertex1 : Red (32 -> 62 in 2 sec) Green (32 -> 132 in 2 sec) Blue (32 -> 164 in 2 sec
+;    ((32 64 2) (32 132 2) (32 164 2))
+;    ((32 64 2) (32 132 2) (32 164 2))
+;    ((0 255 2) (0 255 2) (64 255 2))))
 
-;; jet shooting up
-(defparameter *jet-vertices* 
-  '((0 0 -0.2) (-0.2 0 0.2) (0.2 0 0.2) (0 (0 0.4 1) 0)))
+;(defparameter *jet-vertices* 
+;  '((0 0 -0.2) (-0.2 0 0.2) (0.2 0 0.2) (0 (0 0.4 1) 0)))
 
 (defmethod draw ((object engine-object) time) 
   (if (< (- time (start-time object)) (activation-time object)) ;; hack since times are in templates!!!
diff --git a/model.lisp b/model.lisp
index 4cd797d..046f0a9 100644
--- a/model.lisp
+++ b/model.lisp
@@ -78,9 +78,12 @@
 (setf (gethash "lime" *colors*) '(0 255 0))
 
 (setf (gethash "orange" *colors*) '(255 165 0))
+(setf (gethash "yellow" *colors*) '(255 255 0))
+(setf (gethash "purple" *colors*) '(128 0 128))
 
 (setf (gethash "black" *colors*) '(0 0 0))
 (setf (gethash "white" *colors*) '(255 255 255))
+(setf (gethash "grey" *colors*) '(128 128 128))
 
 
 ;; returns a model of a 3 pyramid from points and colors