F-5B runway length ??
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Originally Posted by hval
US Herk,
The wings differed between the T-38 and the F-5 in the following ways: -
1/ The wing of the T-38 meets the fuselage straight and ends square (refer to page 10 of this linked document. Ignore the wing fences. The F5 wings do not; they have leading edge root extensions. See Here
2/ The F-5 has leading edge root extensions and wingtip launch rails for missiles. The LERX help at high alpha with stall speeds.
3/ the T-38 wing is constructed of honeycomb material while the wing of the F-5 family uses conventional skin over underlying support structure
The wings differed between the T-38 and the F-5 in the following ways: -
1/ The wing of the T-38 meets the fuselage straight and ends square (refer to page 10 of this linked document. Ignore the wing fences. The F5 wings do not; they have leading edge root extensions. See Here
2/ The F-5 has leading edge root extensions and wingtip launch rails for missiles. The LERX help at high alpha with stall speeds.
3/ the T-38 wing is constructed of honeycomb material while the wing of the F-5 family uses conventional skin over underlying support structure
There are some shots of F-5Es performing restricted-runway operations here.
Or so I am told. If you can make it through the opening segments and still think about aeroplanes, I have news for you.
Or so I am told. If you can make it through the opening segments and still think about aeroplanes, I have news for you.
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HVAL
All of the Barrier or Cable traps were on landing and were pretty low weight and speed. Hot climate, yes usually but some were in a ME winter. There were a few take off abort traps with lots of things hung on the wings that go bang (usually after release) and base altitude was about 2500ft. Only other thing I would add is that the F5E wasn't cleared for an approach cable.
All of the Barrier or Cable traps were on landing and were pretty low weight and speed. Hot climate, yes usually but some were in a ME winter. There were a few take off abort traps with lots of things hung on the wings that go bang (usually after release) and base altitude was about 2500ft. Only other thing I would add is that the F5E wasn't cleared for an approach cable.
I recall that the F-5E's operated by the RMAF had a nose wheel extension n that was activated on line up. don't think the F-%B models ' had this.. They certainly used alot lot less runway than oor Mirage 111's.
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US Herk,
The wings were basically the same "thickness" - 4.8% thickness ratio.
The f-5A wing is basically a single assembly that goes across the aircraft centreline. It is aluminium alloy multi spar construction. Some wing components are bonded aluminium honeycomb (these include leading edge flaps, the outboard trailing section, flaps and aileron trailing sections, outboard leading edge and the area above the main gear strut wells, along with main gear strut doors and aileron access doors).
During the life time of the F-5 (nearly two thirds of F-5's built were still active in 2005) there were modifications and different models with differing designs. Upgrades included modifications to wings. For instance The F-5E has a wing area more than 9% greater than that of the F-5A. One thing to be aware of is the fact that there were some considerable differences in models, including airframes. The F-20, for instance had one jet engine (GE f404).
The T-38 considered LERx, leading edge flaps, etc as unnecessary to its basic training duties, although the wings of both aircraft are of essentially the same planform.
Like the F-5, the T-38A uses a single-piece wing. On the Talon Trailing edge plain flaps drop next to the fuselage to increase drag and lift for low speed flight. The wing was of a honeycomb construction.
The T-38 airfoil was a NACA 65A004.8 with 1 percent chord contrast leading edge droop modified with .65 (50) camber from 0-40 percent chord. A very thin wing, it had an overall thickness ratio of just 4.8 percent and a span-to-thickness ratio of 51.1. The wing span was just 25.25 feet (7.696 m) in contrast to the aircraft length of 46.37 feet (14.1 m).
The wing had a mean aerodynamic chord (MAC) of 7.73 feet (2.356 m) and an aspect ratio (AR) of just 3.75. It was trapezoidal in shape with a planform area of 170 square feet. The leading edge wing sweep was 32 degrees, and the quarter-chord wing sweep was 24 degrees. Dihedral and incidence angles were both 0 degrees.
The F-5A had a maximum weight of 20,040 lbs (9090 kg). The T-38A had a maximum weight of 12,050 lbs (5,466 kg). The F-5A top speed was 925 MPH, the T-38A top speed was 820 MPH
The T-38 was so swift that its original main landing-gear retraction system proved insufficient to get the main wheels retracted before the accelerating jet reached the maximum gear-down speed of 240 knots. Since forcing the air- craft to stay slower than 240 knots while the gear retracted was considered unacceptable because it would mean reducing power after takeoff or establishing a steeper climb out angle, the Northrop team devised a way to help the main gear retract faster. The thin wing precluded installing a larger hydraulic retraction system with- out bulging its contours. This had an undesirable outcome on aircraft performance-drag. It was possible to gain some increase in retraction system power by modifying the existing system within the confines of the airframe shape, but the final answer to the retraction speed was the creation of a hinged flap on the trailing edge of the main landing gear strut doors. These hinged flaps aerodynamically boost- ed the retraction of the main gear. A simpler mechanical linkage eventually replaced the original hydraulic door flap; versions of it served the various F-5 models as well.
By the way one F-5 variant everyone forgets is the X-29.
The wings were basically the same "thickness" - 4.8% thickness ratio.
The f-5A wing is basically a single assembly that goes across the aircraft centreline. It is aluminium alloy multi spar construction. Some wing components are bonded aluminium honeycomb (these include leading edge flaps, the outboard trailing section, flaps and aileron trailing sections, outboard leading edge and the area above the main gear strut wells, along with main gear strut doors and aileron access doors).
During the life time of the F-5 (nearly two thirds of F-5's built were still active in 2005) there were modifications and different models with differing designs. Upgrades included modifications to wings. For instance The F-5E has a wing area more than 9% greater than that of the F-5A. One thing to be aware of is the fact that there were some considerable differences in models, including airframes. The F-20, for instance had one jet engine (GE f404).
The T-38 considered LERx, leading edge flaps, etc as unnecessary to its basic training duties, although the wings of both aircraft are of essentially the same planform.
Like the F-5, the T-38A uses a single-piece wing. On the Talon Trailing edge plain flaps drop next to the fuselage to increase drag and lift for low speed flight. The wing was of a honeycomb construction.
The T-38 airfoil was a NACA 65A004.8 with 1 percent chord contrast leading edge droop modified with .65 (50) camber from 0-40 percent chord. A very thin wing, it had an overall thickness ratio of just 4.8 percent and a span-to-thickness ratio of 51.1. The wing span was just 25.25 feet (7.696 m) in contrast to the aircraft length of 46.37 feet (14.1 m).
The wing had a mean aerodynamic chord (MAC) of 7.73 feet (2.356 m) and an aspect ratio (AR) of just 3.75. It was trapezoidal in shape with a planform area of 170 square feet. The leading edge wing sweep was 32 degrees, and the quarter-chord wing sweep was 24 degrees. Dihedral and incidence angles were both 0 degrees.
The F-5A had a maximum weight of 20,040 lbs (9090 kg). The T-38A had a maximum weight of 12,050 lbs (5,466 kg). The F-5A top speed was 925 MPH, the T-38A top speed was 820 MPH
The T-38 was so swift that its original main landing-gear retraction system proved insufficient to get the main wheels retracted before the accelerating jet reached the maximum gear-down speed of 240 knots. Since forcing the air- craft to stay slower than 240 knots while the gear retracted was considered unacceptable because it would mean reducing power after takeoff or establishing a steeper climb out angle, the Northrop team devised a way to help the main gear retract faster. The thin wing precluded installing a larger hydraulic retraction system with- out bulging its contours. This had an undesirable outcome on aircraft performance-drag. It was possible to gain some increase in retraction system power by modifying the existing system within the confines of the airframe shape, but the final answer to the retraction speed was the creation of a hinged flap on the trailing edge of the main landing gear strut doors. These hinged flaps aerodynamically boost- ed the retraction of the main gear. A simpler mechanical linkage eventually replaced the original hydraulic door flap; versions of it served the various F-5 models as well.
By the way one F-5 variant everyone forgets is the X-29.
Last edited by hval; 22nd Apr 2012 at 13:37. Reason: I saw two US Herks
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Area Rule
AGS Man,
Thanks for that. I would say that the F-5 was an extremely clean aircraft. It very closely followed Whitcombs' principles for area rule. This was initially due to jet engines not being as possible as they might be. In later models of the F-5, with jet engine developments, and with changes in the F-5 design the area rule requirement was not adhered to as strictly.
Originally the Northrop team designed the F-5/T-38 airframe to meet Mach 1.0 standards. Wind tunnel tests showed it was good for mach 1.15.
Thanks for that. I would say that the F-5 was an extremely clean aircraft. It very closely followed Whitcombs' principles for area rule. This was initially due to jet engines not being as possible as they might be. In later models of the F-5, with jet engine developments, and with changes in the F-5 design the area rule requirement was not adhered to as strictly.
Originally the Northrop team designed the F-5/T-38 airframe to meet Mach 1.0 standards. Wind tunnel tests showed it was good for mach 1.15.
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Well, I can vouch for it being quick to accelerate to gear limiting speed - a problem during cold weather. Summer time, not quite as bad. One had to be quick to get the gear moving up almost as soon as you broke ground.
A fun plane to fly. At the time (and it may still), it had the quickest roll rate in the USAF inventory...some 720 deg/sec. Continuous aileron rolls with greater than 3/4 stick deflection was a prohibited maneuver in the flight manual as it was prone to roll coupling...something many solo students probably explored.
A fun plane to fly. At the time (and it may still), it had the quickest roll rate in the USAF inventory...some 720 deg/sec. Continuous aileron rolls with greater than 3/4 stick deflection was a prohibited maneuver in the flight manual as it was prone to roll coupling...something many solo students probably explored.
