Can someone explain the seemingly big drop of payload capacities of New Glenn from LEO's 45t to GTO's 13.6T? That is GTO/LEO=30% for a two staged rocket. Falcon 9 FT is 36.8%. Although Kerosine 1st stage gives Flcon 9 advantage, but Hydrolox 2nd stage should give New Glenn advantage too. So I would expect New Glenn to be at least equal to Falcon 9 or even better (if payload does not scale linearly with overall mass).
BTW, the figures for New Glenn are from their user guide and are final design spec, not temparory figures of prototyping.
The claim that the Falcon Heavy rocket has a LEO (Low Earth Orbit) payload capacity of 70 tons is misleading.
The Falcon Heavy shares nearly the same fairing diameter and height as the Falcon 9 rocket. While there were plans to increase the fairing height, they appear to have failed. This means the payload volume for both the Falcon Heavy and Falcon 9 is almost identical.
In rocketry, a critical parameter is the **length-to-diameter ratio**, which partially determines the core stage’s ability to safely fly under maximum dynamic pressure. For the Falcon 9, a 3–4-meter-class rocket, this ratio is approximately 21, approaching its design limit. Larger-diameter rockets inherently face lower maximum safe length-to-diameter ratios because their relative wall thickness decreases as diameter increases. Since the Falcon Heavy’s core stage is nearly identical to the Falcon 9’s, its payload volume is effectively capped.
The Falcon 9’s actual payload volume can typically accommodate a single standard satellite weighing 8–10 tons for GTO (Geostationary Transfer Orbit). Only with high-density payloads like Starlink "blade" satellites—which use ion thrusters to drastically reduce fuel volume—can it achieve over 18 tons of payload capacity.
Thus, the Falcon Heavy’s stated "70 tons to LEO" refers to the total mass delivered to LEO, which includes the payload, the second stage, and additional second-stage fuel. Compared to the Falcon 9, the Falcon Heavy retains significantly more second-stage fuel during orbital insertion—potentially up to 40 tons more.
This explains why the Falcon Heavy’s actual payloads to date have not exceeded 10 tons. Beyond this threshold, neither the Falcon 9 nor Falcon Heavy can physically fit larger payloads within their fairings. The Falcon Heavy’s primary role is for deep-space missions, with most payloads ranging between 3–6 tons. The heaviest payload to date, a module for the Lunar Gateway, weighed around 10 tons.
In contrast, the **New Glenn** rocket, with its 7-meter diameter, far surpasses the Falcon Heavy in practically useful payload capacity for space missions—whether to LEO, GTO, or beyond. Similarly, China’s **CZ-10** (Long March 10) outperforms the Falcon Heavy in real-world payload capacity. The CZ-10 is a three-stage rocket; in its two-stage configuration with a CBC (Common Booster Core) setup, its fairing can exceed 25 meters in height, further enhancing its payload capabilities.
