You are correct about RGHP.
A little bit about our motivation, which is simplicity, specifically increasing reliability and lowering costs through simplification of designs and manufacturing. That's something that seems to be a rare motivation in the industry. To support our business model, we rejected cryogenic propellants as well as ignition systems. There are other areas as well, such as the type of pumps we will be using (I can't talk about that - yet). We also use commonality, such as the prop systems on all three stages are related and of the same family.
We need restart capability, which with hypergols, esp. peroxide can have a long ignition lead. We're addressing that with our fuel mixture. We're addressing the lower performance of RGHP through our engine design and operating parameters. Chamber cooling uses a unique form of regen design.
-------- Original Message --------
Subject: [AR] Re: Introduction to Aphelion Aerospace and a new RGHP
system
From: Norman Yarvin <yarvin@xxxxxxxxxxxx>
Date: Fri, October 01, 2021 1:19 pm
To: arocket@xxxxxxxxxxxxx
On Fri, Oct 01, 2021 at 11:58:10AM -0700, Matthew Travis wrote:
>... a new “green” non-toxic and environmentally-friendly hypergolic
>bipropellant in an operational system. This will enable very low
>system cost, minimal infrastructure requirements and low launch
>costs. A lot of our tech is proprietary but I can say that our
>oxidizer uses RGHP and the fuel is NOT petroleum-based (e.g. RP1,
>Kerosene, etc.).
I take it RGHP is "rocket grade hydrogen peroxide"?
To me, the main market for hypergolics seems like it's orbital
maneuvering. Brief pulses of thrust which have to be precise are a
scenario where self-ignition can be a big plus, and since less fuel is
involved, fuel cost is less of an issue. For most uses, though, torch
igniters seem quite satisfactory.