Ask any veteran GTA San Andreas player to name the single most infuriating optional mission in the game, and nine out of ten will immediately shout: "Supply Lines..."
Given by tech nerd Zero at his RC electronics hobby shop in Garcia, San Fierro, this mission puts Carl Johnson in control of a miniature remote-controlled "RC Baron" biplane equipped with machine guns. Your task is to track down and eliminate five of Berkley's commercial couriers traveling across San Fierro and pilot the aircraft safely back to Zero's rooftop before your fuel meter empties.
Between sensitive pitch-and-roll flight controls, narrow city alleyways, and an aggressive fuel decay meter, players frequently crash or run out of gas just yards from the finish line. This guide reveals the hidden fuel mechanics of the RC Baron, outlines a proven zero-fail flight route, and explains how landing on roads turns this nightmare mission into an easy victory.
Mission Briefing & Objectives
- Mission Giver: Zero (RC Shop, Garcia, San Fierro)
- Required Vehicle: RC Baron (Miniature gasoline-powered model airplane)
- Primary Objective: Destroy 5 couriers (3 vans, 1 motorcycle, 1 scooter) and return to the rooftop.
- Failure Conditions: The fuel gauge drops to zero before landing, or the RC Baron explodes from crash damage or enemy gunfire.
- Prerequisite: You must complete Air Raid (defending Zero's transmitters with a minigun) to unlock this mission.
The Fuel Mechanics Secret: Original PS2 Bug vs Modern Ports
To understand why this mission developed such a terrifying reputation, you must understand how fuel consumption changed across game versions:
The Original PS2 Bug (v1.0)
On the original 2004 PlayStation 2 release, the fuel meter was programmed with a fatal math error: it behaved like a flat countdown timer, draining constantly at the exact same speed whether you were full throttle or gliding silently. The only way fuel stopped dropping was coming to a full, stationary halt on the ground.
The Fixed Modern System (PC, Mobile, Definitive)
In all modern ports (PC v2.0+, Android, iOS, and The Definitive Edition), Rockstar fixed the code. Fuel now depletes only when actively holding the throttle button or firing the machine guns. When you release the gas and glide, fuel consumption drops to virtually zero!
Mastering the Gliding Technique: Save 50% More Fuel
Now that you know fuel is tied to your accelerator key, you can exploit the gliding mechanic to finish the mission with over half your fuel tank intact:
- Climb in Bursts: Tap the accelerator in short 2-second bursts to gain altitude, then release the throttle completely. The RC Baron possesses high aerodynamic lift and can glide several city blocks with zero fuel loss.
- Never Hold Throttle Downhill: Whenever descending down San Fierro's steep hills, keep your finger completely off the gas. Steer with gentle rudder adjustments.
- Stop Accelerating in Tight Turns: Banking while holding the throttle burns triple fuel and causes wide turning circles. Let off the gas before initiating turns.
The Ground Attack Tactic: Land and Shoot (Game-Changer)
The hardest part of this mission is trying to aim dual machine guns from the air while the RC plane wobbles in crosswinds. The couriers will return fire with pistols, shredding your plane's health bar.
The secret method is treating the RC Baron like a remote-controlled car:
- Fly ahead of a courier van and land directly on the asphalt street right in front of or behind the vehicle.
- Once on the ground, the RC plane handles like a miniature go-kart. Taxi forward using light throttle taps.
- Open fire with your machine guns point-blank into the engine grill or tires. Stationary ground fire delivers 100% bullet accuracy, causing courier vans to explode in less than four seconds.
- Once the van explodes, back away to avoid blast damage, tap full throttle to take off, and head toward the next target.
The Optimal 5-Courier Target Elimination Sequence
Eliminating targets in the wrong geographic order forces you to fly back and forth across the entire map, running out of fuel over the ocean. Follow this proven circular route:
Immediately after launching from Zero's roof, bank slightly right and dive southward down the street. The first delivery van is driving right past Zero's building. Land behind it and blow it up before it leaves the neighborhood.
Head north toward downtown. Motorcycles are high-priority targets because they travel fast and can cross grass lawns. Glide above the biker, line up your nose, and fire a burst. One single hit will knock the rider off the motorcycle, leaving him helpless on foot.
Turn west toward Hashbury. The third courier rides a slow Pizzaboy scooter. Because his vehicle has low top speed, you can easily dive from behind and eliminate him with a quick spray of machine gun fire.
Fly east toward the industrial shipyard area. Land on the long straightaway road behind the van, match his speed on the ground, and shoot his gas tank until the van catches fire.
The final van is traveling south, putting him on a direct path back toward Zero's shop! Intercept him as he navigates intersections, destroy the vehicle, and prepare for your return flight.
How to Safely Land on Zero's Rooftop
The mission is not over until your wheels come to a complete halt inside the red corona on Zero's rooftop:
- Approach the rooftop from a wide angle, aligning your plane with the long axis of the roof.
- Cut the throttle 50 yards out and let gravity pull the plane down gently.
- Do not dive nose-down at the last second, as hitting the rooftop antenna or bouncing off the brick rim will explode the plane.
- Touch down with your rear landing gear first, brake to a stop inside the red cylinder, and claim your victory!
What Actually Fails Supply Lines (and What Doesn't)
Knowing the real rules takes a lot of stress out of this mission:
- Only two things fail it: the RC Baron running out of fuel, or the plane being destroyed. Using the plane's self-destruct also ends the mission, so don't touch it by accident.
- The police can't stop you. Your wanted level is switched off for this mission, and the sheriff's deputies in Rangers won't shoot at the plane, even if you shoot them. Ignore them and save your fuel for the couriers.
- Get behind each courier. The game's own prompt tells you to "line up the RC Baron behind the courier". Attacking from behind keeps the target in your gun line for longer than a side-on pass.
- There are five courier groups to destroy before they complete their deliveries, then you fly back to Zero's roof.
If it still feels impossible, you're in good company: Zero's voice actor, David Cross, has said he couldn't beat the original version of this mission. It's optional for the story, but you need it for 100% completion and to unlock New Model Army, which turns Zero RC into a $5,000-a-day asset.
Asset Revenue and Mission Rewards
| Reward Element | Value | Benefit |
|---|---|---|
| Direct Cash Payout | $5,000 Cash | Immediate mission reward |
| Subsequent Mission | New Model Army | Final Zero RC asset mission |
| Business Asset Value | $5,000 Daily Payout | Generates passive cash outside shop |
| 100% Requirement | Mandatory Asset | Required for 100% completion stat |
Video Walkthrough: Supply Lines
Frequently Asked Questions
Is Supply Lines required for 100% completion in GTA San Andreas?
Yes! While Zero's missions are marked with a "Z" icon and are not required to beat the main storyline to see the credits, Zero's RC Shop is an official business asset. You must complete Supply Lines to acquire the asset and hit 100% game completion.
How do you save fuel in Supply Lines?
Release the accelerator button whenever cruising or descending hills. On all modern versions, fuel only depletes while actively accelerating or firing weapons. Gliding consumes zero fuel.
Can you drive the RC Baron on the ground?
Yes! Landing on the road behind targets allows you to drive the plane like a car and fire directly into courier vans with 100% accuracy, saving tremendous fuel and avoiding aerial aiming struggles.
What is the next mission after Supply Lines?
The third and final mission in Zero's chain is "New Model Army," where you pilot an RC Goblin helicopter to remove barrels, build metal bridges, and destroy rival tanks for Zero's RC Bandit.
Why was Supply Lines so hard on PlayStation 2?
The original v1.0 PS2 game contained a fuel timer bug that drained fuel continuously regardless of whether you accelerated or glided. This bug was corrected in all subsequent PC, Android, and remastered releases.