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  1. Doggzilla

    Raptor Composite Aircraft

    Actually this is a perfect example of what I’m talking about. A close friend of a relative is a project manager for a large aerospace company, and the number one major issue is his subordinates arrogance. Nobody knows everything about aircraft. Nobody. Even the best engineers still work in...
  2. Doggzilla

    Raptor Composite Aircraft

    The reason he doesn’t listen is because he’s being told 20 different ways and has no idea which one is correct. I find that even well proven topics are often full of overwhelming amounts of incredibly misleading BS. Getting accurate information is like herding cats.
  3. Doggzilla

    Modern day "motorcycle of the air" aircraft class?

    Well, it doesn’t have a cockpit so it’s customary to include sack choppers instead.
  4. Doggzilla

    Modern day "motorcycle of the air" aircraft class?

    Interesting Chinese flying motorcycle. Appears to have 8 motors in push/pull configuration.
  5. Doggzilla

    Raptor Composite Aircraft

    The performance he is trying to achieve is roughly the same efficiency as a B-17, so it’s definitely achievable. But I’m not sure with the power plant he has selected. A GM 6.2/6.5 diesel is the same weight (After the PSRU and accessories are taken into account) and capable of the same power at...
  6. Doggzilla

    Raptor Composite Aircraft

    The issue with divergence isn’t obvious until you do a little math on it. Lets say the total cross section of the aircraft is 150 sq ft when looking from below. Let’s say 90ft sq is behind the CG and only 60 is ahead. This appears to be very statically stable with so much area behind the CG...
  7. Doggzilla

    Raptor Composite Aircraft

    The concern is not nonlinear lift, it’s that at high AoA the higher cross section of the nose may cause divergence.
  8. Doggzilla

    Replacing VTOL fans and turbines with combustion cans

    Well the J79 had an operational bleed system that worked well even at reduced throttle during landing. That is where I would start. Very well proven on the F-104. https://en.wikipedia.org/wiki/Blown_flap
  9. Doggzilla

    What do you guys think of LIQUID runways?

    As far as ground permeability is concerned, a few thousand feet of plastic lining is a heck of a lot cheaper than any other runway material. Especially at a remote location. As far as total mass is concerned, if it requires a 30 foot dam to make a 2000-3000 foot lake, consider having to move an...
  10. Doggzilla

    What do you guys think of LIQUID runways?

    Went to an air museum years ago and they had a water runway dug into the ground for a massive 1930s seaplane they used to fly. In a lot of areas that operate amphibs this actually seems easier than leveling a runway. Especially if the terrain is rough. It’s a lot easier to build a small dam nd...
  11. Doggzilla

    Replacing VTOL fans and turbines with combustion cans

    Afterburners have a very low pressure ratio. The compressed air from the turbine is roughly 10 times higher compression ratio. It would be vastly more efficient than an afterburner.
  12. Doggzilla

    Replacing VTOL fans and turbines with combustion cans

    Even in turbojets there is enough excess air. The F-104 and Mig-21 both had enough excess air to run blown flaps even at low power settings. The supply of air is not an issue. It’s been tried and proven long ago.
  13. Doggzilla

    Replacing VTOL fans and turbines with combustion cans

    This is already mentioned. The excess compressed air that most turbines produce but cannot utilize due to overheating concerns. Most turbines compress several times what they can actually burn.
  14. Doggzilla

    Replacing VTOL fans and turbines with combustion cans

    Instead of running complex fans or additional lift turbines, how about just supplying compressed air and having a combustion can at the nozzle? The air supply systems themselves are very well proven in aircraft with blown wings and flaps, like the F-104 and even a C-130 was once equipped with...
  15. Doggzilla

    Experimental Ducted Fan Aircraft Designs

    Was doing some math and it appears that ducted fans become much more suitable as weight increases. The F-5 is considered one of the cheapest jets to operate, so I will use it as a reference point. For a ducted fan to reach the same gross weight it would require 1500-1600hp. A 1500-1600hp...
  16. Doggzilla

    Ducted fan aircraft

    This exactly. The major benefit of having these aircraft should be similar to Green Berets. To allow training of friendly forces. Drones are somewhat vulnerable to jamming, which the US can counter easily. But this is not to case for most of our third world Allies. A cheap turboprop aircraft...
  17. Doggzilla

    Ducted fan aircraft

    I’m betting it mostly is because of the effectiveness of gunships lately. I’ve heard nothing but raving reviews from anyone who has been involved with them. They would probably have a smaller gunship if anything met the criteria. But the twin market is really limited right now. And many of the...
  18. Doggzilla

    Ducted fan aircraft

    It would definitely help it’s cruise performance. The original turbine is extremely inefficient and loses power quickly with altitude. The original turbine is so inefficient that even the PT-6 is 30-40% more efficient and more powerful at cruising altitude. Almost anything is better than what...
  19. Doggzilla

    Ducted fan aircraft

    Was just reading about the USAF buying some turboprops to test for light attack roles and realized that an upgraded fantrainer would actually have significant advantages over the turboprops. It has vastly better outside vision, and it also has a nose that isn’t taken up by a prop. Allowing a...
  20. Doggzilla

    Cessna tests new “Skycourier” and it’s actually not too terrible

    That’s actually the only reason Elon Musk was able to succeed. His true talent is cost cutting. If something is unreasonably expensive he will have his engineers build it in-house for a fraction of the cost. This seems backwards to most professionals because it would appear to incur massive...
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