Firefly speed challenge!

[Eclipse 32]

go as fast as you can in atmosphere with Firefly installed, and take pictures!

[umbra humanus]

Here is my attempt:

This is early career so I only got to 1413.1 m/s  before my cockpit started to overheat.

[Eclipse 32]

you don't need to be career, FYI

[umbra humanus]

Quote

you don't need to be career, FYI

I know. I  decided to do this in my career mode install, because I had a contract to break mach 4 anyways.

[DeadJohn]

On 2/7/2025 at 11:22 AM, Eclipse 32 said:

go as fast as you can in atmosphere with Firefly installed, and take pictures!

Are part mods and planet packs allowed?

I'm asking because I once built a jet able to cruise at 3700 m/s for JNSQ Kerbin. IIRC it used an OPT engine, Mk2 Expansion cockpit for heat resistance, and the remainder was stock parts. Maybe I'll recreate it to see how it looks with Firefly.

[Eclipse 32]

yeah, idc what mods you use, as long as you add a modlist to your post!

[Duke MelTdoWn]

Nice challenge! I built a record plane about a year ago for this challenge: forum.kerbalspaceprogram.com/topic/219217-air-speed-record-challenge.

This time around I reached 1938 m/s before melting (the crew is fine). I am only running visual mods, no parts or gameplay changes.

Airspeed Challenger BH on Steam Workshop: https://steamcommunity.com/sharedfiles/filedetails/?id=3041717110

This uses no weird construction techniques except for the heatshields translated to the front.

I think I can go faster if I am allowed to exploit the stock aerodynamic system? (Fairing occlusion abuse to make the plane essentially drag less, heatshield lift, cap rear of Rapiers with rotated and translated nosecone, ...)

[Duke MelTdoWn]

With the drag optimized version 'Airspeed Challenger HE' I could reach 2017 m/s before melting the wings off, a new personal best.

The trick is to use very little wing, this is basically a Rapier with elevons strapped to it. Tune the angle of attack of the elevons so you can fly prograde without gaining too much altitude. This maximizes the thrust of the Rapier. At the same time, flying prograde reduces drag and heat load. Before I had problems with the Rapier melting.

This uses some fishy construction techniques. Root is a service bay, the airstream fairing is attached to the inside of the service bay. This reduces the drag of the service bay to zero. Fuel tanks are in the airstream fairing. Rapier is attached to the back of service bay. Shock Cone is attached to back of Rapier and rotated. This reduces the drag of the Rapier and heat load on the Shock Cone.

This whole plane only produces ~ 55 kN of drag at Mach 6 and 4000 meters. TWR at Mach 3 is 13.5 because it only weights 3.6 tons. No passengers.

Edited Thursday at 04:38 PM by Duke MelTdoWn

[Eclipse 32]

oh, i forgot to mention,  if you yeet through the atmosphere during aerobraking, that counts

also, you don't have to stay on Kerbin. you can fly through Jool at stupid Km/s for all i care, as long as you take pics!