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Harrier legs experiment...


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I decided to a little experiment to test the combat radius of the Harrier. I've seen a quoted 300nm combat radius but no idea of what flight profile or loadout was used to get to that number.

 

So, I decided to test a lo-lo-lo profile, carrying 2 bags, 2 GBU 32 , 2 Sidewinders, ECM & Gun pods. Flew in a straight line mostly, at around 500 feet AGL and at 110 FFPM, which gave me 330Knots/0.5M . I set my bingo fuel to 5900lbls. I jettison the bags when they where empty and the bombs when I reached bingo, then I turned back. 

 

During the return leg, I adjusted the FFPM to 100 for 360Knots. I landed with 1000Lbls of fuel left. 

 

297mn was my measured "combat" radius... No fancy maneuvering to evade anything or throttle up to do a bomb toss or anything...  

 

Not bad... I thought the AV8B would have shorter legs... I bet that we could squeeze a bit more out of it with more careful flight planning and different flight profile and loadout.

 

This sortie was about 1 hour 40 mins....

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Not bad for staying low, quite a respectable radius for a basic straight line jaunt with no push and pull.

Try a hi-lo-hi, lo section at minimum 420kts, max 480kts for around 40 mile ingress to tgt, egress same distance. Load out is fairly universal so keep that.

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3 hours ago, Draken35 said:

I decided to a little experiment to test the combat radius of the Harrier. I've seen a quoted 300nm combat radius but no idea of what flight profile or loadout was used to get to that number.

 

So, I decided to test a lo-lo-lo profile, carrying 2 bags, 2 GBU 32 , 2 Sidewinders, ECM & Gun pods. Flew in a straight line mostly, at around 500 feet AGL and at 110 FFPM, which gave me 330Knots/0.5M . I set my bingo fuel to 5900lbls. I jettison the bags when they where empty and the bombs when I reached bingo, then I turned back. 

 

During the return leg, I adjusted the FFPM to 100 for 360Knots. I landed with 1000Lbls of fuel left. 

 

297mn was my measured "combat" radius... No fancy maneuvering to evade anything or throttle up to do a bomb toss or anything...  

 

Not bad... I thought the AV8B would have shorter legs... I bet that we could squeeze a bit more out of it with more careful flight planning and different flight profile and loadout.

 

This sortie was about 1 hour 40 mins....

 

Ok so for your range quoted you would meet this range if you had 1000lB additional in ordanance (6x snakeyes for example) but the caveat to that is you'd have to be crusing at sea level of around mach .4 in the real bird.  At mach .5 you would expect your range to drop to circa 275 yet i note you had less weight and you landed with a good reserve.  The lo lo lo profile generally allows for a 150 second from brakes off max continuous thrust (+15 at short lift wet rating), tank dropped when empty, a 5 minute max mil thrust on ingress and egress from target and leaving a reserve of 5% initial plus 10 minutes at sea level loiter on return.  Perhaps refly in this manner and i would suggest that your range will be below parameters.  

 

I have made some comments on the razbam discord as there are issues currently with the Harrier.  I was i think the first one to voice issues when it was apparent the fuel flow had been tanked to which they then released the patch with the engine improvements however the jet is still off on many aspects of its performance data.  I couldnt believe it had been passed by the SME so i did ask if it had been tested by their SME given its a "final" model (re patch notes) as on my tests around a month ago it could not reach real world parameters with basic endurance.  The response i got back was reassuringly that he / she hadn't (which is pretty obvious).

 

I left it with them that i wasnt going to comment on any further aspects of Hi-Lo-Lo-Hi, Hi-Hi-Hi, Lo-Lo-Lo or CAS standard operations until they had actually had their SME fly the module.  Otherwise its pointless.

 

Personally speaking i do not think flight models should be released into Open Beta prior to SME validation as it just makes a mockery of the entire product.  I do wonder sometimes if Razbam think they they will not get picked up on shortcomings and its acceptable to just put out what a coder thinks is right (which is often wrong).  The model also has issues with its EM state, fuel flow in general and certain flight characteristics (a real easy one to spot is in level flight roll full stick to port, around the longitudinal horizontal axis noting its roll rate keeping level flight, then foll to starboard - notice the difference in rates, also some very interesting g readings lol).  Repeat with SAS off also and some very interesting results.

 

Anyway as i indicated lets allow Razbam to test with their SME as its definatly has to be a work in progress at the moment, as this cannot be final as they indicated in their patch notes.  Well not unless they are serious about modelling the actual aircraft.  I also look forward to some of the sub systems being correctly modelled also.

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Edit - sorry in summary i should have stated the range would be bang on for Lo-Lo-Lo if the aircraft had followed the criteria i mentioned above.

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4 hours ago, Hawkeye_UK said:

 

Ok so for your range quoted you would meet this range if you had 1000lB additional in ordanance (6x snakeyes for example) but the caveat to that is you'd have to be crusing at sea level of around mach .4 in the real bird.  At mach .5 you would expect your range to drop to circa 275 yet i note you had less weight and you landed with a good reserve.  The lo lo lo profile generally allows for a 150 second from brakes off max continuous thrust (+15 at short lift wet rating), tank dropped when empty, a 5 minute max mil thrust on ingress and egress from target and leaving a reserve of 5% initial plus 10 minutes at sea level loiter on return.  Perhaps refly in this manner and i would suggest that your range will be below parameters.  

 

I have made some comments on the razbam discord as there are issues currently with the Harrier.  I was i think the first one to voice issues when it was apparent the fuel flow had been tanked to which they then released the patch with the engine improvements however the jet is still off on many aspects of its performance data.  I couldnt believe it had been passed by the SME so i did ask if it had been tested by their SME given its a "final" model (re patch notes) as on my tests around a month ago it could not reach real world parameters with basic endurance.  The response i got back was reassuringly that he / she hadn't (which is pretty obvious).

 

I left it with them that i wasnt going to comment on any further aspects of Hi-Lo-Lo-Hi, Hi-Hi-Hi, Lo-Lo-Lo or CAS standard operations until they had actually had their SME fly the module.  Otherwise its pointless.

 

Personally speaking i do not think flight models should be released into Open Beta prior to SME validation as it just makes a mockery of the entire product.  I do wonder sometimes if Razbam think they they will not get picked up on shortcomings and its acceptable to just put out what a coder thinks is right (which is often wrong).  The model also has issues with its EM state, fuel flow in general and certain flight characteristics (a real easy one to spot is in level flight roll full stick to port, around the longitudinal horizontal axis noting its roll rate keeping level flight, then foll to starboard - notice the difference in rates, also some very interesting g readings lol).  Repeat with SAS off also and some very interesting results.

 

Anyway as i indicated lets allow Razbam to test with their SME as its definatly has to be a work in progress at the moment, as this cannot be final as they indicated in their patch notes.  Well not unless they are serious about modelling the actual aircraft.  I also look forward to some of the sub systems being correctly modelled also.

Hawkeye, can you post what the mission profile , speeds/alts and loadout was for your test? I looked but I'm useless with Discord. 

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5 hours ago, Hawkeye_UK said:

 The lo lo lo profile generally allows for a 150 second from brakes off max continuous thrust (+15 at short lift wet rating), tank dropped when empty, a 5 minute max mil thrust on ingress and egress from target and leaving a reserve of 5% initial plus 10 minutes at sea level loiter on return. 

 

Why does people always drop the fuel tank, when real pilots say that it is not allowed unless emergency?

Meaning you take-off with the fuel tanks, you land with the fuel tanks, even when they are empty through whole mission. 

 

So unless you are jumped on and you need to defend yourself, or you get to emergency where you need to again drop ordinance, you are to hold on those and suffer the drag... 

As even when those are simple and fairly cheap ($ 5000-15000 or so each) tanks, if everyone would be dropping them once empty the fleet would not have any in couple days.

 

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13 minutes ago, Fri13 said:

Why does people always drop the fuel tank, when real pilots say that it is not allowed unless emergency?

HI.

Good one, had no idea 🙄. In my case I drop them because it shortens the time when refueling, as getitng new tanks is faster than refilling them. Will lok at it from now on...

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10 hours ago, Fri13 said:

 

Why does people always drop the fuel tank, when real pilots say that it is not allowed unless emergency?

Meaning you take-off with the fuel tanks, you land with the fuel tanks, even when they are empty through whole mission. 

 

So unless you are jumped on and you need to defend yourself, or you get to emergency where you need to again drop ordinance, you are to hold on those and suffer the drag... 

As even when those are simple and fairly cheap ($ 5000-15000 or so each) tanks, if everyone would be dropping them once empty the fleet would not have any in couple days.

 

 

Couldn't agree more the only reason for dropping would be,

 

1) Pre planned - Operating on the very limit of endurance and required to fulfil primary tasking of strike (although this would be devolved through the ATO and given to another platform so in itself would be some emergency action)

2) Unplanned ground operations with Troops in contact and in a position of being overun and requiring emergency additional loiter time until additional CAS platforms can brought to the AO, either for direct strike, show of force, awaiting Medevac etc.

3) Inflight emergency, either through damage sustained to aircraft from hostile action or birdstrike causing instability or equally things such as unexpected fuel burn performance through various technical issues or unanticipated and adverse winds aloft (again unlikley with modern metar forecasts).  However given a primary concern of running out fuel and not being able to RTB or divert your likely to have a tanker divert anyway.

4)Engaged and bounced by hostile aircraft (again unlikely given who the Harriers are operated by, there is CAP present)

 

There seems to be some mystical myth amongst the community that dropping tanks suddenly give you a massive range increase, its not true on the Harrier.  Reality is on this type of loadout id only expect a 20NM mission radius difference on a Lo-Lo-Lo sortie with jettisoning the tanks taking it just north of 290NM mission radius at max range mach 0.4 flight profile, hence why its not viable to drop them.  This holds true pretty much through the mach spectrum.  Equally on a CAS typical profile of say 200 NM radius from homeplate an extra 10 mins on station (either side of 100 mins).  However away from the OP's original point on a typical CAS profile flight with hi transit operating on max range you'd squeeze out an additional circa 50 NM on mission radius.

 

 

Anyway i see all the time F16's taking off with 10 CBU97's or 6 and 6 Mav D's on public servers so dropping the tanks on a Harrier its the least of our issues lol.   


Edited by Hawkeye_UK
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Why does people always drop the fuel tank, when real pilots say that it is not allowed unless emergency?

 

Because in DCS, those tanks are free and there is an unlimited number of them available.

 

Like so many things commonly done in DCS, the real world is somewhat different.

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On 5/28/2021 at 5:57 AM, Fri13 said:

 

Why does people always drop the fuel tank, when real pilots say that it is not allowed unless emergency?

Because we aren't real pilots (most of us anyway) and we do not know what we do not know...But now I know. 

 

I didn't want to open a can of worms with the topic. I just was looking for a number I could use for a mission that I'm planning and decided to share the results and methods. 

 

I can see in my near future a test of much does the empty bags impact there range at low, medium and high altitude...

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