DCS: F-5E actual celing

[DaveRindner]

Reported celing of F-5E is around 51K feet. Source below:

https://www.fighter-planes.com/info/f5.htm

 

In DCS 2.5, starting from Instant Action/F-5E/Take Off from Batumi in winter, using full afterburner and shallow climb I am unable to breach 39,200 feet (calibrated) altitude. Nor can the aircraft sustain flying altitude in trimmed level flight above 38,500 ft. (calibrated). This is with clean airframe, flaps on auto, and fuel at slightly below 1/2. Let me just add, with me at the controls. I got DCS: F-5E only in December '17.

Would like to hear what others attained in their F-5E self training.

Thank you

 

Cheers

[BIGNEWY]

what is your total weight?

 

Manual reports service ceiling ( at 14000 lbs weight ) 54000ft or 16460m

[DaveRindner]

Good question. Not exactly certain. Except I begin my ceiling attempt with fuel slightly less then 1/2 in both tanks. Otherwise aircraft is clean. No tanks, no weapons, no pylons.

[DaveRindner]

Isn't wind a component of KIAS or TAS, affecting ground speed. Headwind requires more power to maintain ground speed , to navigate correctly, as flight nav between any two waypoints is essentially dead reckoning. Conversely a tailwind pushes the aircraft, requiring less power to maintain ground speed. In flight nav coursework, I beleive that is referred to as 'computing offsets'. I recall a presentation on this by Cpt.Dale Brown (USAF Ret.), on work of navigator/WSO/OSO in F-111, B-52, and B-1B, on YT back in 2008(?). However I am unable to locate that vid today.

Not to deviate from thread,carrier recovery is likewise aided by relative headwind. For recovery ops, carrier steams a course, such that landing strip (on angled decks) is pointed into the wind. With carrier doing 20 knots, and 10 knots wind, creates 30 knots (34.5 mph) wind over deck. If recovering aircraft is landed at 150 knots KIAS to the pilot, the ground speed at ramp would be 120 knots. I hope I have this right.

 

Good point , on your part, about climbing into head and tail winds.

What I am experiencing is at 38,500 - 39K indicated alt. My KIAS drops below 130 and airframe starts to shake in prestall, and begins descending with 20+ AOA. Even if I trim elevators to max, keep in full AB, I am unable to keep AC in level flight at altitude above 38,500.

What I am asking is what is the maximum altitude that others have reached?

Edited February 6, 2018 by DaveRindner

[Martini]

Isn't wind a component of KIAS or TAS, affecting ground speed. Headwind requires more power to maintain ground speed , to navigate correctly, as flight nav between any two waypoints is essentially dead reckoning. Conversely a tailwind pushes the aircraft, requiring less power to maintain ground speed. In flight nav coursework, I beleive that is referred to as 'computing offsets'. I recall a presentation on this by Cpt.Dale Brown (USAF Ret.), on work of navigator/WSO/OSO in F-111, B-52, and B-1B, on YT back in 2008(?). However I am unable to locate that vid today.

Not to deviate from thread,carrier recovery is likewise aided by relative headwind. For recovery ops, carrier steams a course, such that landing strip (on angled decks) is pointed into the wind. With carrier doing 20 knots, and 10 knots wind, creates 30 knots (34.5 mph) wind over deck. If recovering aircraft is landed at 150 knots KIAS to the pilot, the ground speed at ramp would be 120 knots. I hope I have this right.

 

Good point , on your part, about climbing into head and tail winds.

What I am experiencing is at 38,500 - 39K indicated alt. My KIAS drops below 130 and airframe starts to shake in prestall, and begins descending with 20+ AOA. Even if I trim elevators to max, keep in full AB, I am unable to keep AC in level flight at altitude above 38,500.

What I am asking is what is the maximum altitude that others have reached?

 

I think that's why he referred to it as a 'bug' - a constant head/tailwind should not impact KIAS.

[RED]

Did you check the altitude in F2? F2/F10 shows object height and not calculated altitude.

DCS shows wrong altitudes in cockpit because of miscalculated pressure! Unfortunately the error gets bigger when you fly higher.

 

See here:

https://forums.eagle.ru/showthread.php?t=200013

 

What temperature did you set in the mission?

[DaveRindner]

39K with headwind. 42K with tailwind.

Yep, thats pretty much the same as I get.

[mayo25]

 At 08.04 it passes at 51000Ft.

[Tiger-II]

Wind should make ZERO difference to aircraft performance! The aircraft only cares about the air through which it flies; not how fast it is passing over the ground (even some RW pilots screw this up severely).

 

Ensure the temperature and pressure are standard (+15 deg. C at sea level and 29.92 in.Hg.), as this WILL affect the aircraft performance.

 

The F-5 still has a problem with either a lack of thrust and/or too much drag.

 

It's still hard to accelerate to Mach 1.4 in level flight (actually, impossible, and even accelerating faster than Mach 1.0 in level flight is very hard). The real aircraft CAN do this, and pilot reports are that it is "easy".

 

Our F-5 is still grossly under-performing.

Edited February 22, 2021 by Tiger-II

[Ironhand]

 

Deleted the content. When I posted, I hadn't realized this thread had been necroed. Getting to 55,000+ feet isn't a problem. If it was back in 2018, it isn't now.

 

Edited February 25, 2021 by Ironhand