Alan J,
XB-42, Los Angeles to Washington DC nonstop at 433 MPH on a day when winds at altitude were below expectation (flightplan for 445)
I've always admired the aerodynamics of the DH 98 series and the way its performance was improved over the five years of development and engine uprating. I'm also aware that its loss rate attributable to structural failures was approximately three times that of the next worse RAF aircraft (attributed in reports to poor glue bond design)
The Douglas XB-42 did not benefit from a comparable long period of flight testing and improvements, and flew only with its original Allison V-1710-125 engines of 1325 HP. The Mosquito prototype with 310 more horsepower and half the weight of the XB-42, after nearly a year of development showed a maximum speed of 388 MPH , the Mixmaster demonstrated 410 MPH on its fourth test flight. With the ultimately intended turbocharged variants, speed at altitude was expected to exceed 470 MPH. Long range (3600 miles) cruise with the single stage Allisons was 312 MPH lugging 4000# half way. (Edit- I don't know where in a mission the 312 would be measured. Even with the single stage Allisons, the flight would be a step climb, with altitude increasing as weight diminished to maintain constant lift coefficient.- possibly throttling back as well for the same reason. Let's assume the speed is just prior to the over-target dash, with payload and return fuel load on board.)
Maybe we should have defined "Bomber" in this thread. The '42 was designed to deliver a bomb load of between 4000 and 8000 pounds over a distance (for the smaller payload) of 1800 miles -this is out and back. I understand that a modified Mosquito could carry a 4000 pound payload, but how far?
Dynasoar
XB-42, Los Angeles to Washington DC nonstop at 433 MPH on a day when winds at altitude were below expectation (flightplan for 445)
I've always admired the aerodynamics of the DH 98 series and the way its performance was improved over the five years of development and engine uprating. I'm also aware that its loss rate attributable to structural failures was approximately three times that of the next worse RAF aircraft (attributed in reports to poor glue bond design)
The Douglas XB-42 did not benefit from a comparable long period of flight testing and improvements, and flew only with its original Allison V-1710-125 engines of 1325 HP. The Mosquito prototype with 310 more horsepower and half the weight of the XB-42, after nearly a year of development showed a maximum speed of 388 MPH , the Mixmaster demonstrated 410 MPH on its fourth test flight. With the ultimately intended turbocharged variants, speed at altitude was expected to exceed 470 MPH. Long range (3600 miles) cruise with the single stage Allisons was 312 MPH lugging 4000# half way. (Edit- I don't know where in a mission the 312 would be measured. Even with the single stage Allisons, the flight would be a step climb, with altitude increasing as weight diminished to maintain constant lift coefficient.- possibly throttling back as well for the same reason. Let's assume the speed is just prior to the over-target dash, with payload and return fuel load on board.)
Maybe we should have defined "Bomber" in this thread. The '42 was designed to deliver a bomb load of between 4000 and 8000 pounds over a distance (for the smaller payload) of 1800 miles -this is out and back. I understand that a modified Mosquito could carry a 4000 pound payload, but how far?
Dynasoar
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