Test pilot admits the F35 cant dogfight

The F-35 compared with other modern jets.
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by element1loop » 03 Mar 2016, 17:33

Ack! :mrgreen: That's a nice warhead, thank you sferrin.


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by basher54321 » 03 Mar 2016, 19:10

armedupdate wrote:Is the F-35's acceleration better or the same or less than F-16. I believe this shows the F-35's acceleration is slightly less. Are the fighters loaded or not?


The comments given out by the pilots don't really tell us much without the context behind it:

RNLAF (Gladys Knight)HTTP://AIRHEADSFLY.COM/2016/01/26/DUTCH-LIGHTNING-TESTERS/
“Even so, slow-speed and high angle-of-attack performance is much better than many fourth generation fighters like the F-16. High angle of attack testing has been an eye-opener for previous F-16 pilots, who are not used to very good slow speed performance. Straight line acceleration is also much better.

RNLAF (Col De Smit) Air Int Vol 88
When comparing performance, I would say that the F-35 turns like an F-16 with pylon tanks; but it climbs, descends & accelerates like a clean F-16.

So although they appear contradictory it's likely they are both actually telling the truth - e.g. Knight could be referring to A-G configuration.
An F-16 with wingtanks also accelerates "like" a clean F-16 under M1.0 but over that you get a massive amount of drag that will slow it down compared to the F-35.

There is also the issue of what F-16 are you comparing with? In the earlier leaked report the Block 40 likely had a better T/D & T/W over the F-16AMs used by the RNLAF.


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by armedupdate » 03 Mar 2016, 20:52

Is there huge difference between straight line acceleration and turning acceleration?

So basically I read, the F-35 is better at everything except sustained turn rate?


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by wrightwing » 03 Mar 2016, 21:08

derphurf wrote:
armedupdate wrote:
derphurf wrote:The F35 in WVR combat really sounds just like a Hornet. Especially in a multiple bandit or 2 v 2, 3 v 3 engagement, it seems like the F-16 should be able to hold its own or more if it sticks to energy fighting basics. Any Hornet that can't keep up with its nose pointing is going to get nailed by gun or AIM-9X.

The problem is the F-35 has similar acceleration to the F-16. The reason why the F-16 can do nasty speed tricks against the Hornet because it retains energy much better. However against the F-35, the F-35 is similar but the F-35 has better AoA and deceleration. So the F-35 is more capable than the F-16 in that reguard.


Based on talks by F35 drivers, the F-16 still holds the advantage in retaining energy, however. Any high AOA manuever you do automatically puts you in a lower energy state

That's if the F-35 driver uses high AoA. The F-16 doesn't have that option. The F-35 can do EM or high AoA.


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by basher54321 » 03 Mar 2016, 22:09

armedupdate wrote:Is there huge difference between straight line acceleration and turning acceleration?


Yes a lot. When you turn a lot more drag is created so you are more likely to decelerate in a turn than accelerate.


armedupdate wrote:
So basically I read, the F-35 is better at everything except sustained turn rate?



Based on what has gone so far the places where the F-35A likely shines in performance over F-16 types.

Transonic & Supersonic acceleration and climb (All internal configs apart from light A-A)
Max speed (All internal configs apart from light A-A)
Max ITR (at slower speeds)
50 degree production AoA limit
Nose authority and control at high AoA


Even with the new information the overall assessment hasn't really changed much.

The F-35C would likely have the same traits but likely be better at high AoA handling and have a better Max ITR. I don't expect it to accelerate / climb like the F-35A though.
Last edited by basher54321 on 03 Mar 2016, 23:56, edited 1 time in total.


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by armedupdate » 03 Mar 2016, 22:38

So when the quotes say the F-35 turns worse than the F-16(turns like F-16 with tanks) they don't mean the F-35 has poorer turning acceleration?


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by geforcerfx » 03 Mar 2016, 22:52

armedupdate wrote:So when the quotes say the F-35 turns worse than the F-16(turns like F-16 with tanks) they don't mean the F-35 has poorer turning acceleration?


I am no expert, so the experts feel free to correct me. But from what have seen ( airshows and flight sims) you don't usually accelerate in a high itr turn, usually I would decellerate until i was producing enough thrust to maintain speed at that turn rate (this is in a sim). The f-35 might have a slower speed at the same turn rate as a f-16, that be what they refering too.

The F-35C would likely have the same traits but likely be better at high AoA handling and have a better Max ITR. I don't expect it to accelerate / climb like the F-35A though.


There a quote frm a test pilot ( I think beesley) saying the C had the best sustained. I think that will change in 3f where the A has full capabilty and the C is still at 7g vs 9g


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by optimist » 03 Mar 2016, 23:24

armedupdate wrote:Is there huge difference between straight line acceleration and turning acceleration?

So basically I read, the F-35 is better at everything except sustained turn rate?

throw some tanks and a bomb on the f-16 and see it's turn rate from the f-16 flight manual online. it won't be pretty.
Europe's fighters been decided. Not a Eurocanard, it's the F-35 (or insert derogatory term) Count the European countries with it.


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by basher54321 » 03 Mar 2016, 23:31

geforcerfx wrote:
There a quote frm a test pilot ( I think beesley) saying the C had the best sustained. I think that will change in 3f where the A has full capabilty and the C is still at 7g vs 9g


Do you have the quote? because 5000 lbs heavier, loads more drag with the same engine!! says to me good luck with that :D

When talking about sustained turns - that is ability by definition for an aircraft to pull a turn while sustaining the same energy (altitude + Speed) level. So no pulling 9G instead of 7G wont actually affect sustained turn rates at speeds where you expect BFM to typically happen (because the G required to sustain is normally much lower).


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by armedupdate » 03 Mar 2016, 23:37

Isn't climb rate comparison a good comparison of acceleration?


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by Dragon029 » 03 Mar 2016, 23:50

Here's a way to look at it, in order to match the same turn rates (remembering that a turn rate is the change in your flight vector, not how fast you can point your nose), the F-35 has to utilise higher angles of attack than the F-16, just simply because things like body lift are more reliant on higher angles of attack to generate the necessary pressure differences, energised vortex flows, etc.

During a quick turn, that higher angle of attack of the F-35 results in a larger amount of drag; in other words, it's lift-to-drag ratio is lower than that of the clean or lightly loaded F-16's. Now here's the thing; this isn't a linear relationship; it's something like this (with the specifics dependent on the design of the wing and airframe):

Image

When an F-35 drops its nose / decreases its angle of attack however and powers out of a turn, drag drops dramatically and the F-35's lift-to-drag ratio and thrust-to-drag ratios increase to put it on a similar footing to a clean F-16.

To reiterate; when you're at a high angle of attack, you're going to bleed energy (unless you're moving at a low airspeed and have a lot of thrust; think of a Hornet doing a slow, high alpha pass at an airshow). The core difference between the F-16 and F-35 is that to attain the same turn rates, the F-35 needs to use a greater angle of attack, although the F-35 has the advantage of being able to continue increasing its angle of attack until it reaches its maximum lift (note: not the same as maximum lift-to-drag) angle of somewhere around 40 degrees. That (as already established) allows the F-35, like the Super Hornet and a few other fighters, to snap it's nose up, to rapidly get its guns on the enemy, albeit for a short period and at the expense of airspeed.


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by basher54321 » 04 Mar 2016, 00:00

armedupdate wrote:So when the quotes say the F-35 turns worse than the F-16(turns like F-16 with tanks) they don't mean the F-35 has poorer turning acceleration?



In a horizontal turn (for example) you can accelerate (gain energy) if you are not turning by much. But if you decide to turn more and keep pulling back on the stick eventually you will start decelerating even at max thrust (losing energy). However there is a point in between this where you neither gain or lose airspeed thus you sustain the turn at the same speed.


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by castlebravo » 04 Mar 2016, 00:27

basher54321 wrote:
armedupdate wrote:So when the quotes say the F-35 turns worse than the F-16(turns like F-16 with tanks) they don't mean the F-35 has poorer turning acceleration?



In a horizontal turn (for example) you can accelerate (gain energy) if you are not turning by much. But if you decide to turn more and keep pulling back on the stick eventually you will start decelerating even at max thrust (losing energy). However there is a point in between this where you neither gain or lose airspeed thus you sustain the turn at the same speed.


It should also be pointed out that this slight decrease in sustained turn rate compared to the F-16C will only exist when the Viper is lightly loaded, and the difference will be quite small compared to the large advantage in high AoA performance the F-35A enjoys.


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by endre » 04 Mar 2016, 08:01

An aspect that many forget here is that F-16s (at least our old models) also carry other systems with them beyond weapons and fuel on actual missions, such as a self-defence jammer and a targeting pod. These also place restrictions on the aircraft, but on the F-35 those same capabilities are included in the basic design, and can naturally be carried without any additional penalty.
Public Affairs, Norwegian F-35 Program Office


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by tincansailor » 06 Mar 2016, 09:52

This report is the best news supporters of the F-35 have gotten in a long time. All fighter pilots train to use the strengths of their aircraft vs. a known opponent. It shows any F-35 critic willing to listen that Lightning II pilots will have a load of tools in their bag of tricks. We've always known the F-35 had superior low speed maneuverability, and could operate at a much higher AoA then any other current fighter, but to hear it can out preform the F-16 in most areas is very impressive.

I've always suspected the F-35 could out dive the F-16, which should give it more options to execute Yo Yo Attacks, or to just get the hell out of Dodge. Now we see it has many options in taking on the F-16, or any other opponents. I'd like to see the F-35 take on the F-18E and beat it at it's own High AoA game. If it can do that it should be able to handle the various SU-27 derivatives. By the time the Indian's return to Red Flag with their SU-30MKI's the F-35A should be a participant. The post mortem on those encounters should be very interesting.


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