diff --git a/84_Super_Star_Trek/rust/src/commands.rs b/84_Super_Star_Trek/rust/src/commands.rs
index 3239b45e..0675ee4f 100644
--- a/84_Super_Star_Trek/rust/src/commands.rs
+++ b/84_Super_Star_Trek/rust/src/commands.rs
@@ -1,8 +1,20 @@
 use crate::{model::{Galaxy, Pos, COURSES, EndPosition}, view, input};
 
+pub fn perform_short_range_scan(galaxy: &Galaxy) {
+    if galaxy.enterprise.damaged.contains_key(view::keys::SHORT_RANGE_SCAN) {
+        view::scanners_out();
+        return;
+    }
+
+    view::short_range_scan(&galaxy)
+}
+
 pub fn get_amount_and_set_shields(galaxy: &mut Galaxy, provided: Vec<String>) {
 
-    // todo check for damaged module
+    if galaxy.enterprise.damaged.contains_key(view::keys::SHIELD_CONTROL) {
+        view::inoperable("Shield Control");
+        return;
+    }
 
     view::energy_available(galaxy.enterprise.total_energy);
     let value = input::param_or_prompt_value(&provided, 0, "Number of units to shields", 0, i32::MAX);
@@ -10,6 +22,7 @@ pub fn get_amount_and_set_shields(galaxy: &mut Galaxy, provided: Vec<String>) {
         view::shields_unchanged();
         return;
     }
+
     let value = value.unwrap() as u16;
     if value > galaxy.enterprise.total_energy {
         view::ridiculous();
@@ -29,17 +42,31 @@ pub fn gather_dir_and_speed_then_move(galaxy: &mut Galaxy, provided: Vec<String>
         return;
     }
 
-    let speed = input::param_or_prompt_value(&provided, 1, "Warp Factor (0-8)?", 0.0, 8.0);
+    let course = course.unwrap();
+
+    let mut max_warp = 8.0;
+    if galaxy.enterprise.damaged.contains_key(view::keys::NAVIGATION) {
+        max_warp = 0.2;
+    }
+
+    let speed = input::param_or_prompt_value(&provided, 1, format!("Warp Factor (0-{})?", max_warp).as_str(), 0.0, 8.0);
     if speed.is_none() {
         view::bad_nav();
         return;
     }
+    
+    let speed = speed.unwrap();
+
+    if speed > max_warp {
+        view::damaged_engines(max_warp, speed);
+        return;
+    }
 
     move_klingons_and_fire(galaxy);
     if galaxy.enterprise.destroyed {
         return;
     }
-    move_enterprise(course.unwrap(), speed.unwrap(), galaxy);
+    move_enterprise(course, speed, galaxy);
 }
 
 fn move_enterprise(course: u8, warp_speed: f32, galaxy: &mut Galaxy) {
diff --git a/84_Super_Star_Trek/rust/src/main.rs b/84_Super_Star_Trek/rust/src/main.rs
index 1b9a0522..ecde0476 100644
--- a/84_Super_Star_Trek/rust/src/main.rs
+++ b/84_Super_Star_Trek/rust/src/main.rs
@@ -26,9 +26,9 @@ fn main() {
             continue;
         }
         match command[0].to_uppercase().as_str() {
-            "SRS" => view::short_range_scan(&galaxy),
-            "NAV" => commands::gather_dir_and_speed_then_move(&mut galaxy, command[1..].into()),
-            "SHE" => commands::get_amount_and_set_shields(&mut galaxy, command[1..].into()),
+            view::keys::SHORT_RANGE_SCAN => commands::perform_short_range_scan(&galaxy),
+            view::keys::NAVIGATION => commands::gather_dir_and_speed_then_move(&mut galaxy, command[1..].into()),
+            view::keys::SHIELD_CONTROL => commands::get_amount_and_set_shields(&mut galaxy, command[1..].into()),
             _ => view::print_command_help()
         }
 
diff --git a/84_Super_Star_Trek/rust/src/model.rs b/84_Super_Star_Trek/rust/src/model.rs
index 4f5a65ac..a078df05 100644
--- a/84_Super_Star_Trek/rust/src/model.rs
+++ b/84_Super_Star_Trek/rust/src/model.rs
@@ -1,4 +1,4 @@
-use std::{ops::{Mul, Add}, fmt::Display};
+use std::{ops::{Mul, Add}, fmt::Display, collections::HashMap};
 
 use rand::Rng;
 
@@ -37,7 +37,7 @@ impl Klingon {
 
 pub struct Enterprise {
     pub destroyed: bool,
-    pub damaged: bool, // later this could be by subsystem
+    pub damaged: HashMap<String, f32>,
     pub quadrant: Pos,
     pub sector: Pos,
     pub photon_torpedoes: u8,
@@ -147,7 +147,7 @@ impl Galaxy {
             quadrants: quadrants, 
             enterprise: Enterprise { 
                 destroyed: false,
-                damaged: false,
+                damaged: HashMap::new(),
                 quadrant: enterprise_quadrant, 
                 sector: enterprise_sector,
                 photon_torpedoes: 28,
diff --git a/84_Super_Star_Trek/rust/src/view.rs b/84_Super_Star_Trek/rust/src/view.rs
index 02c72815..68934549 100644
--- a/84_Super_Star_Trek/rust/src/view.rs
+++ b/84_Super_Star_Trek/rust/src/view.rs
@@ -1,5 +1,15 @@
 use crate::model::{Galaxy, Pos, EndPosition, SectorStatus};
 
+pub mod keys {
+    pub const SHORT_RANGE_SCAN: &str = "SRS";
+    pub const NAVIGATION: &str = "NAV";
+    pub const SHIELD_CONTROL: &str = "SHE";
+
+    pub const ALL_SYSTEMS: [&str; 3] = [
+        SHORT_RANGE_SCAN, NAVIGATION, SHIELD_CONTROL
+    ];
+}
+
 pub fn enterprise() {
     println!("
 
@@ -82,7 +92,7 @@ pub fn short_range_scan(model: &Galaxy) {
     let mut condition = "GREEN";
     if quadrant.klingons.len() > 0 {
         condition = "*RED*";
-    } else if model.enterprise.damaged {
+    } else if model.enterprise.damaged.len() > 0 {
         condition = "YELLOW";
     }
 
@@ -195,3 +205,16 @@ pub fn shields_set(value: u16) {
 pub fn shields_hit(shields: u16) {
     println!("      <Shields down to {shields} units>")
 }
+
+pub fn inoperable(arg: &str) {
+    println!("{} inoperable", arg)
+}
+
+pub fn scanners_out() {
+    println!("*** Short Range Sensors are out ***")
+}
+
+pub fn damaged_engines(max_warp: f32, warp_factor: f32) {
+    println!("Warp engines are damaged.  Maximum speed = warp {max_warp}
+    Chief Engineer Scott reports, 'The engines won't take warp {warp_factor} !'")
+}