B29 with jet engines.

As I was watching a 1990’s era Discovery Wings documentary on the B29, I had a thought.
What if a variant with Jet engines was developed (say using J31 or J33).
Sure the big ass engine nacelles of the ‘29 could take it.
Does not have to be standard production. Just a variant used in special roles.
High speed Recce. Maybe the nuclear attack.
 
Might be able to put one jet engine under each wing, so they can wack it up a bit when on a bombing run?

Or more importantly help with take off - B29 take off unlike most bombers was not a quest for altitude it was a quest for airspeed before (not if) the engines overheated and caught fire and melted the wing off - in order to generate enough cooling

It was such a problem that pre take off checks like magneto drop checks (where each of the 2 magnetos on each engine was switched off in series and the drop in RPM should not drop below a particular %) was done while taxiing to the runway

Perhaps some thing like was done with the Avro Shackleton MR3 - two 2,500 lbst Viper turbojets, one in the rear of each outboard nacelle
 
Or more importantly help with take off - B29 take off unlike most bombers was not a quest for altitude it was a quest for airspeed before (not if) the engines overheated and caught fire and melted the wing off - in order to generate enough cooling

Of the faults the Convair B-32 had, overheating wasn't one of them.
I knew a pilot who was part of the B-32 Program, and his thoughts on the matter was that Boeing screwed that up on the B-29. Said that B-32 had much more cooling flap area on the nacelles, and that fully extended, even acted as a sort of airbrake. They also used the Curtiss-Electric props, like the Silverplate rather than the Hamilton Standard.
 
The KB-50 tanker variant did have two J-47 jets to make it easier to refuel jet fighters. The B-50 was essentially a B-29 with bigger engines (Pratt and Whitney Wasp Majors), a larger tail, and a stronger wing, features which made mounting jets possible.

1280px-Boeing_KB-50J_in_flight.jpg
 

mottajack

Banned
I thought of the KB-50 tankers, too, only after I posted about the B-36H.

some KC-97s (also sons of the B-29 like the B-50) also had jet engine pods.

in the end B-29s could have been fitted with a pair of jet engines. But the B-29 already had a lot of troubles in 1943-1944, and jets also had their shares of issues.
 
By the time you added the weight of the jet engines, the fuel tanks for jet fuel, what would be the net takeoff boost gain? Also, there will be a range penalty for the extra weight and possibly less fuel for the radials due to the need for separate jet fuel.
 
By the time you added the weight of the jet engines, the fuel tanks for jet fuel, what would be the net takeoff boost gain? Also, there will be a range penalty for the extra weight and possibly less fuel for the radials due to the need for separate jet fuel.

On the Shackleton it was only used to get off the deck so its not going to need that much fuel and jet engines are light compared to ICE engines and it built into the Nacelle so not creating excess drag etc

What it does is allow a greater MTWA - so in the cas eof the Shak MR3 more kit, more fuel, more weapons etc than would otherwise be the case
 
By the time you added the weight of the jet engines, the fuel tanks for jet fuel, what would be the net takeoff boost gain? Also, there will be a range penalty for the extra weight and possibly less fuel for the radials due to the need for separate jet fuel.

On the B-50s and B-36s that used jets, the jets were modified to use avgas to eliminate the need for separate jet fuel tanks and equipment.

Typically, the jets would be used on takeoff- the B-36 in particular had extremely long takeoff rolls, and switched off for cruising. They would be turned on again for the sprint over the target- in the case the B-36, so the aircraft could get out of the way of the blast from a 15mt H-bomb.
 
Oh Boeing study a B-29 with jet Engine or Turbo prob engines
But during Working on that, they got Data from German Windtunnel testing during ww2
What let to complet new Design of Aircraft: The B-47 and later B-52 Bomber
Far bettet as WW2 Based B-29 variants
 
By the time you added the weight of the jet engines, the fuel tanks for jet fuel, what would be the net takeoff boost gain? Also, there will be a range penalty for the extra weight and possibly less fuel for the radials due to the need for separate jet fuel.
The turbines on those were set to run on avgas, so no separate tankage.
found this
Flight testing of the KB-50J began in April of 1957. The aircraft was able to make successful hookups and fuel transfers at higher altitudes, at greater gross weights, and at higher airspeeds than was possible with the KB-50. The jet engines increased the maximum speed to 444 mph at 17,000 feet at a gross weight of 179,500 pounds. In addition, the jet engines shortened the takeoff distance by 30 percent, and improved the time to climb to refueling altitude by 60 percent.
without the J47 under each wing, the max takeoff was 173,000 pounds, Each pod was around 3000 pounds
 
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