Fast Hawk

[scr1]

Is this the fastest Hawk

https://www.bbc.co.uk/news/uk-england-norfolk-55825159

[Bigpants]

In the early days of the Hawk I believe a few pilots did push the high speed dive to see if it would go supersonic. I recall some of the old hands like Dougie Mee saying not to bother as it became rather unstable in the transonic region. The English Electric Lightning on the other hand would slip through Mach 1 with ease in cold power as I came close to doing over Louth Lincs in 1985. I thought the recent boom incident was a QRA scramble?

[Bob Viking]

It was actually very common to go supersonic in the Hawk.

Back when I was a student on 208 Sqn (2002) it was a standard part of the student night flying syllabus. We would climb to 45000’, roll inverted and point out towards the Irish Sea until the CSI said M1.0.

There were some interesting handling characteristics to be aware of but nothing scary.

I was never a Hawk T1 air test pilot but I was (am) on the Hawk T2. I can’t vouch for the T1 test schedule but I can say that on the T2 the idea is to get close to, but not exceed, the Mach.

I also remember a load of screen grabs on the wall in the Ops room at 419 Sqn (CFB Cold Lake) showing that a Hawk 115 had comfortably exceeded the Mach. I can’t remember exactly how much by though.

So, these things happen (accidental boomers) and yes the Hawk can do it but you need to try quite hard!

BV

[Non Linear Gear]

Damm having my earphones in. F15s were doing their normal stuff over the house today. Supersonic Adour over Narfalk! Bet the test pilot will have a chat with the boss or Harry.

[Miles Magister]

Back in the day when the Hawks were relatively new into service going supersonic was a programmed syllabus sortie flown during the day as part of the course. It needed a shallow dive and from memory we had to exceed M1.2 to be truly supersonic. I think we achieved M1.3 but my memory is fuzzy after all this time.

MM

[Ken Scott]

So, these things happen (accidental boomers) and yes the Hawk can do it but you need to try quite hard!

When I did AFT on the Hawk it was part of night flying, I had completed my ‘ME lead-in’ cse by that point so didn’t get to break M1...

During one of the earlier sorties looking at transonic handling I was enjoying the cobblestones & the tail wagging when my QFI told me to slow down, we were at M0.99 & overland. We were at max chat & in a shallow dive so I can’t imagine it would have taken much more to ‘break the sound barrier’.

It would be another 30 years before I did get to finally break it, in a Typhoon.

[H Peacock]

The Mach run was one of the few things you could do at night. I recall having to be over the sea, and pointing away from land during the run. Quite a pitchy ride with the main altimeter showing an Off flag because it couldn't keep up with displaying the correct altitude as it unwound! Wasn't 1.2 the limit in the T1? Recovery to subsonic was even more pitchy!! 🤔

[itsnotthatbloodyhard]

Yes, I’m sure 1.2 was the limit, but it would’ve taken a big effort to get anywhere near it. I don’t think I ever saw more than about 1.06. As Bob says, some of the handling characteristics were ‘interesting’, particularly the differential shockwave formation that could happen around M.96...

[Alex Whittingham]

As Miles says, it was a standard syllabus item at 4 FTS in the eary 80s. Go supersonic in a shallow dive, observe wing drop, back home for tea and cookies.

[BEagle]

We did a boom run both dual and solo on the proper swept-wing trainer, the Folland pocket rocket. Up to FL400 under 'Western Radar', roll inverted and pitch to 30 deg nose down, then roll erect and hold 40 deg. Watch the IMN, no drama, explore the control feel in pitch, then roll left through 300 deg and recover right to S&L. No wrecks, nobody drownded, nothing to laugh at at all. Except for one chap on the course who cocked up the rolling maneouvre and pulled through achieving some colossal IMN value until he recovered at about FL100!

Then a boom run on the Hunter refresher course; even the GT6 wasn't as keen to go supersonic as the Gnat was. Whereas Puddy took me to M1.2-ish in the T7 on an airtest after looking for the Irish ferry - before slowing down to well below 100KIAS with lots of buffeting and general excitement as we were checking out a reported aileron issue.

Whereas the Hawk (or JP 6 as some termed it) had nothing like the pleasant transonic handling of the Gnat / Hunter. Directional stability was a bit weird too, although we didn't have the extended fin trailing edge fillet when I flew it, so that might have been part of the issue.

[Monarch Man]

The Mach run was one of the few things you could do at night. I recall having to be over the sea, and pointing away from land during the run. Quite a pitchy ride with the main altimeter showing an Off flag because it couldn't keep up with displaying the correct altitude as it unwound! Wasn't 1.2 the limit in the T1? Recovery to subsonic was even more pitchy!! 🤔

Similar experiences if memory serves correctly, ahhh the ignorance of youth

[tartare]

Interesting to read... you learn something everyday.
Assumed that it was subsonic and would be damaged if one went that quick...

[swh]

The audio in the opening post sounded more the after effects of baked beans or cabbage.

[just another jocky]

Same for me, back in '85, supersonic run over the sea, solo, but we were told to bunt to around 40deg nose down. Don't recall the MN.

[Bob Viking]

Do you know my least favourite thing about Pprune?

Its when people can find the time to come on here to make incorrect and unsubstantiated claims as if they were scientific fact. However, those same people are never able to find the time to come on and retract their statements or admit they were wrong.

I suppose one should never miss the opportunity to spin a quick WIWOL/WIWOP/WIWOB dit though.

Maybe I just got out of the wrong side of bed this morning.

BV

[Foghorn Leghorn]

Do you know my least favourite thing about Pprune?

Its when people can find the time to come on here to make incorrect and unsubstantiated claims as if they were scientific fact. However, those same people are never able to find the time to come on and retract their statements or admit they were wrong.

I suppose one should never miss the opportunity to spin a quick WIWOL/WIWOP/WIWOB dit though.

Maybe I just got out of the wrong side of bed this morning.

BV

Go on BV, who’s stolen the jam out of your doughnut?

[Bob Viking]

To be fair I’m not in a bad mood. I’ve just been waiting a long time to make that particular whinge. This seemed like an opportune moment.

I feel much better now.

BV

[longer ron]

A Hawk supersonic run was done at least once on TV.
Bang Goes the Theory presenter Dallas Campbell flew in the 'ASTRA' Hawk (XX341) in 2010 with Rhys Williams (Tutor with ETPS),the inside stuff was filmed in the ETPS Heli Hangar (can't remember bldg number) next to the old Control Tower.The Mach run was done over the Brizzle Channel I believe.
There is even a very brief view of my best side out on the flight line during pre taxy Flying Control Checks :eek:

Starts at 6.50
https://www.youtube.com/watch?v=JyOqfwur8mg&ab_channel=Hoolgao

[132bod]

I did it as a 16yo Air Cadet in summer 1978 in the Sim at Valley. After an uneventful takeoff, got reset and told to do continuous roll at 10 degree climb. Did that, got asked if I wanted to go supersonic. Right you're at 40,000ft. Push over into a dive (can't remember how steep) quickly so you stabilise & accelerate before losing too much height & hold the wings level. first attempt, lost control so got reset. 2nd time, -1.5G push into dive, >M1 for 6 sec max M1.06, 6.1G pulling to recovery at approx 5,000ft. Not so good on the ILS landing. At one stage I was 4.7 miles out at 25ft, I think that put me in the middle of Holyhead. It was the only Summer Camp I went on & as I let it be known I was joining-up (planned, & what I did 5 weeks later) I got to do stuff that the other cadets didn't.

[ROC man]

Is there any truth in the rumour that it was traditional for the student pilot doing his first M1 Hawk dive to have a pair of girl friend/ wife knickers in his pocket thus creating supersonic knickers and perhaps signing them as such (if not too lacey)?

[sycamore]

ROC,they probably just wear them...!

[Mogwi]

First time I dropped a bang was in a Jumping Bean T4 on an air test near Düsseldorf. Nobody noticed - or maybe they were used to large bangs from a few years earlier!😈

In in later life, I used to do it pointing at the ship at the end of an air test. 40k, roll inverted and pull. Trick was to recover before exceeding the IAS limit on the big tanks.

Happy days!

Mog (WIWOH!)

[BEagle]

In the early days of the Hawk T Mk 1 at 4FTS, unexplained boom complaints from the Viet Taff were occasionally received by the station.

It turned out that extending the airbrake at high IAS was the cause - I don't know whether it was subsequently fixed?

[Bob Viking]

The best a Hawk T1 can do in terms of IAS is 550 knots.

Sea level, Mach one is approximately 660 knots.

Could an extended air brake at high IAS really cause the airflow to exceed the Mach? Besides which the extent of the airbrake extension would be limited by the high IAS.

I’m not saying you’re wrong it’s just something I’ve never heard before. Surely, if true, it would have been part of the infernal A2 groundschool I was forced to endure?!

BV

[eaw]

Hi BV,

I remember, as a stude on 4 FTS in the late 70s, the kerfuffle caused by using the airbrakes at high subsonic speed leading to mini booms all over north Wales. This seemed to mainly occur during GH aeros and tailchases.
The instruction we were given was to roll & pull buffet to reduce speed, rather than use airbrake to slow, if we were at high ish (> 0.85) mach. This not surprisingly led to some fairly agricultural applications of large G loadings before we were told just to SLOW DOWN (but not told how to!!).

[Bob Viking]

How exactly did you end up doing 0.85 during aeros and GH and especially tail chasing? They must have been some funky manoeuvres.

BV

[CAEBr]

[QUOTE][was to roll & pull buffet to reduce speed, rather than use airbrake to slow, if we were at high ish (> 0.85) mach/QUOTE]

And there in a nutshell is the point at which the seemingly continual tailplane replacement programme across the T1 fleet was born.

[Non Linear Gear]

How exactly did you end up doing 0.85 during aeros and GH and especially tail chasing? They must have been some funky manoeuvres.

BV

And there Iceman places his fist to his mouth and coughs 8 letters with an equidistant spacing.

[ASRAAMTOO]

I seem to remember that on the "High Level" sortie during the Hawk course a loop was flown starting at FL220 and 0.8M

[BEagle]

Which is a mere 360KIAS.....

I can't remember what the 'fix' was as I only did a pre-TWU refresher on the Hawk. But the mini-booms from the airbrake certainly annoyed the locals back then.

[nipva]

I am a bit surprised by the apparent distress to the locals from these 'booms'. From memory from my time at Brawdy as an instructor on both Hawk and Hunter, all medium/upper air exercises were flown well out to sea either to the west or south west. There was no overland area available south of airway G1 and a transit to the north of it was impractical in both time and fuel terms. So these 'booms' would have been generated out to sea well beyond the earshot of Mr Zammett.

[BEagle]

No the reported booms were whilst I was on my pre-TWU refresher at Valley. All 4FTS GH (apart from the high level supersonic exercise) was overland in my time.

[nipva]

Apologies, for some reason I had assumed this was a Brawdy issue not a Valley one. Next time I will read the question!

[orca]

ROC Man.

The ‘tradition’ of carrying underwear on the supersonic run is 100% cast iron fact. On my course one fellow did get the wrong end of the stick and wore them - he was quite the spectacle at the outbrief as his other half was quite petite. I was (sadly) a little sheepish about the practice so I took my favourite soft toy - a rather strange eel about a foot long that doubles as a board cleaner when he wasn’t being a lucky talisman.
That eel was there for everything - supersonic runs, Ops, deck landings...

[alamo]

I flew many air tests at Valley in the early 80s. There was no call in the Air Test Schedule to do a supersonic run. After a timed climb to FL400, it was all gently downhill until the high speed run al low-level - nominally at 2000ft but sometimes a tadge lower!

There was no supersonic run on the FJ course (which I never did [the course]). But I was introduced to them by a venerable colleague who swore that the Hawk did not make a sonic bang; so my first experiences were directed at fields of sheep on the Lleyn.

I was not convinced so whenever I had a go, I checked that I was out to sea and got radar clearance for a "high speed" run. It got to be known around the students and I had no shortage of volunteers to fill the back seat.

It was pretty straight forward: half roll, pull to 45+ degrees nose down and half roll again. Handling and recovery were unremarkable.

The low-level run was more problematic. On some aeroplanes, 167 168 and 169 particularly, approaching 500 kts the turn and slip ball would edge out, and quite a bit or rudder was needed to correct. I took one to Dunsfold to be looked at and remember Andy Jones, the Hawk development TP, approaching the tailcone with a large screwdriver. Swapping the tailcone for the modded one with the large fillet and vertical rear largely eliminated the problem.

[RetiredBA/BY]

I seem to remember that on the "High Level" sortie during the Hawk course a loop was flown starting at FL220 and 0.8M
High level ! Are you serious? Even on the Vampire T11 we started. WAY. higher than that, went over the top at around 35 K, under partial control !! I doubt we started or even finished at .8 Mach though.
That said, the only underwear involvement was a change on landing after a nasty fright, recovering from a high level loop !

The only booms on the Vampire supported the tailplane !

[LOMCEVAK]

I started flying Hawk T1 airtests in the mid-80s and I am sure that the current dive to 0.98M was in the schedule by then. The directional trim change that occurs as you accelerate does vary from airframe to airframe and is associated with the tail cone. If you take the tailcone off, immediately refit it and then fly the dive again it can behave differently so it is very sensitive to rigging. There is inevitably a wing drop during the acceleration that requires about 1/3 lateral stick to maintain wings level although, again, it varies between airframes and there is some correlation with the sideslip due to the directional trim change. The recovery is flown wings level at 2.5g because there is a transonic pitch up during the deceleration and the normal acceleration limit at those Mach numbers is only 4.5g. All of this is fairly classical for a wing of that quarter chord sweep angle. I have to say that on this airtest profile I never felt that there was a particular risk of exceeding 1.0M inadvertently because there was always adequate nose up tailplane authority to reduce the dive angle if the acceleration was too high. However, if an airframe displayed atypical handling characteristics for whatever reason I could see how it could happen.

I have intentionally been to about 1.05M but I am intrigued to know how HS ever achieved the 1.2M limit!

[Just This Once...]

I have intentionally been to about 1.05M but I am intrigued to know how HS ever achieved the 1.2M limit!

I asked JF the same thing and his answer was the aircraft had no true airframe mach limit as the aircraft was effectively self-limiting. The absence of a number didn't sit well with the customer though so the M1.2 number offered by the intake/propulsion team was used instead. The actual maximum achieved by HS was M1.17.

[pontifex]

RETIRED.
You may not remember. We could start the Mk5 at FL350, but then we were not weighed down with unnecessary things like fire extinguishers or bang seats.

[RetiredBA/BY]

RETIRED.
You may not remember. We could start the Mk5 at FL350, but then we were not weighed down with unnecessary things like fire extinguishers or bang seats.
No, sadly, never flew the 5 , they had all left Swinderby by the time of my course, the very last at 8 FTS.

...... But dont knock bang seats, been there done that !!

[teeonefixer]

[QUOTE][[color=#333333]was to roll & pull buffet to reduce speed, rather than use airbrake to slow, if we were at high ish (> 0.85) mach/QUOTE]

And there in a nutshell is the point at which the seemingly continual tailplane replacement programme across the T1 fleet was born.

There has only been one Tailplane replacement program on the Hawk, starting in the late 90's. Nothing to do with airframe buffet alone, the combination of pulling the stick while at moderate "g". The new ones are really robust.