The second N-1 vehicle was launched on 3 July 1969 and carried a modified L1 Zond spacecraft and live escape tower. Boris Chertok claimed that a mass model lunar module was also carried; however, most sources indicate that only the L1S-2 and boost stages were on board N-1 5L. Launch took place at 11:18 PM Moscow time. For a few moments, the rocket lifted into the night sky. As soon as it cleared the tower, there was a flash of light, and debris could be seen falling from the bottom of the first stage. All the engines instantly shut down except engine #18. This caused the N-1 to lean over at a 45-degree angle and drop back onto launch pad 110 East. The nearly 2300 tons of propellant on board triggered a massive blast and shock wave that shattered windows across the launch complex and sent debris flying as far as 10 kilometers (6 miles) from the center of the explosion. Launch crews were permitted outside half an hour after the accident and encountered droplets of unburned fuel still raining down from the sky. The majority of the N-1's propellant load had not been consumed in the accident, and most of what had burned was in the first stage of the rocket. However, the worst-case scenario, mixing of the fuel and LOX to form an explosive gel, had not occurred. The subsequent investigation revealed that up to 85% of the propellant on board the rocket did not detonate, reducing the force of the blast. The launch escape system had activated at the moment of engine shutdown (T+15 seconds) and pulled the L1S-2 capsule to safety kilometers (1.2 miles) away. Impact with the pad occurred at T+23 seconds. Launch Complex 110 East was thoroughly leveled by the blast, with the concrete pad caved in and one of the lighting towers knocked over and twisted around itself. Despite the devastation, most of the telemetry tapes were found intact in the debris field and examined.