I agree the video in post 155 shows a classic high-G, high-speed wing stall (wing drop, and the whole aircraft sinks behind the tree).

But by that moment, the aircraft was almost certainly going to hit the ground, regardless. The "accident" (whatever it was), that put the aircraft in a position where it must hit the ground one way or another, began much earlier in the maneuver. The stall only changed the impact point by a few yards.

The stall may - emphasize "may" - even have been the result of a well-intentioned pull on the controls to try and clear the people-filled highway, and crash in open ground beyond. But physics and aerodynamics are unforgiving...

Reference RAT 5's question about height planning to exit a loop the answer is that it depends since there are a number of variables: entry speed, G on pull up (and pull out), rotational (or autorotational) components within the figure, aircraft performance, density altitude and target exit speed. You may plan to exit at your point of entry, gain height or lose it depending upon your sequence.

All display pilots will have gate heights and, where appropriate, speeds for the key components of their sequences. An individual's display authorisation will stipulate a minimum height for aerobatic figures and fly-by, but it is up to the pilot to set their own limits above these minima for the particular display they are flying. This is particularly relevant where someone has a DA for multiple types, since a single authorisation applies across all categories on your DA. To illustrate the point, you may have an aerobatic piston DA covering everything from a Jungmeister to a P51 Mustang and your base height (for aerobatics and fly past) across all types will be the same. Obviously a loop radius in P51 is much larger than a Jungmeister so the margin of error in feet is significantly greater. One would, or should, adjust one's own personal hard deck accordingly.

Ref: phiggsbroadband, you are correct that strictly a "loop" enters and exits on the same axis. There are many figure variants with loop segments and lines or rolls that change the shape and/ or axis of the figure. It is hard from the video I have seen to ascertain whether the figure flown was a clover or a reverse half cuban but the aerobatic taxonomy is irrelevent in the context of this tragedy. The key risk issue is pulling through the vertical (the reason that a reverse half cuban is a significantly higher risk figure low level than a half cuban).

A few additional points worth making:

• We live in a world where instant answers to everything tend to be demanded, but speculation until the AAIB has completed its investigation is distressing for those involved and completely unproductive.

• There is no complacency within the display flying community or the bodies that regulate us regarding the risks inherent in staging a flying display. On the whole the safety record has been extremely good over the years compared with other higher risk pursuits (such as eventing and motor sports), largely thanks to the professionalism of all involve. Procedures were revised, for example, a couple of years ago for the granting of higher level aerobatic DAs when a relatively inexperienced aerobatic pilot creashed after an unssucessful recovery from a Mulleroid.

• That said, it is unthinkable in my view that the scale of this tragedy will not have an effect on the way things are done in the future. My hope is that everyone involved retains a sense of objectivity and that ultimately the baby isn't thrown out with the bathwater.

My thoughts are with all of the families that have had to deal with the terrible consequences of this weekend's events.

Wing tanks also reduce wing bending moment. Less fatigue.

Correct.

Incorrect.

23 degrees of flap was used on the Hunter for combat manoeuvring, quite normal to use them during aeros.

The UK would have per capita more airshows than any other country on the planet. They have been crashing at airshows and talking about lessons learnt since Don Bullock in the A-26 invader in 1980.
Low level loop, in a fast jet, in close proximity to civilians?
Prove me wrong but the safety record in the USA at air shows is way better.

Combat manoevering, but at slow speed. Trailing edge flaps are never used at high speed, one disadvantage being drag.

Wrong, on the Hunter they are split flaps not trailing edge flaps, different aerodynamic principles, and as for slow speed they could used up to around M 0.9

Another day,

https://en.wikipedia.org/wiki/List_o..._and_incidents.

Have a good read…….

Up to M 0.9!!?

I find that impossible to believe. If true, Sidney Camm must have been unaware ..... who would want to use flaps at Mach 0.9?. They would depart the mainframe at that speed in short order!

Sounds ridiculous!

Shoreham Airshow Crash

BASICS SIMCAS (South East Coast Immediate Care Scheme) volunteer immediate care nurse Tony Kemp was called yesterday to attend the Shoreham Airshow Crash involving a Hawker Hunter Jet. Based at the Airshow assisting the British Red Cross in their crowd medical cover Tony witnessed the immediate aftermath of the crash as the jet crashed onto the A27 dual carriageway just outside the airfield.

Asked to attend the scene Tony was joined by two off duty GPs who had undertaken BASICS training and whose assistance was invaluable in the coming hours. As reported nationally a number of motorists and other road users died at the scene whilst the pilot escaped with his life although remaining critically ill in the Royal Sussex County Hospital. Tony was the first medical resource on scene and was quickly joined by the SECAmb airside ambulance for the airshow.

It was immediately obvious that there were a number of deceased casualties and reports of walking wounded being taken to an ex-pub, now part of the nearby Lancing College that lies adjacent to the A27. Tony split his medical response equipment and one of the GP's was initially tasked to the ex-pub to provide medical care and assessment. Tony and the other GP took the bulk of his kit to the site of the cockpit in the rough ground just off the road bordering the runway to the airfield where there were reports from fire-fighters on scene that the pilot was alive.

Working in cooperation with fire-fighters and about 10-meters from the engines which remained on fire the pilot received immediate life-saving care whilst arriving ambulance crews brought a long board stretcher down to the site so that the pilot could be rapidly extricated to a place of greater safety for all concerned and his care handed over to an air ambulance (HEMS) team. Tony and the GPs, working with other rescuers and in liasion with the the Medical Incident Commander from the Kent Air Ambulance provided care to the walking wounded who were at the ex-pub site and at the main Red Cross treatment centre on the airfield. They were joined by a medical team from the Fire and Rescue Service who brought additional equipment. Four others were transferred to hospital as a direct result of the crash.

Tony and the GPs were reunited at the Airfield in the British Red Cross treatment Centre where sterling work was being done by Red Cross Volunteers caring for not only those physically and emotionally affected by the crash but also a range of non-related injuries and illnesses arising (as normal) within the crowd of 20,000. The Main Treatment Centre had been declared a secondary treatment centre for casualties arising from the crash. Two other Red Cross treatment centres within the venue also cared for a number of others who presented with minor illness and injury as well as upset by the afternoon's events.

Tony said afterwards: "My medical colleagues and I were so impressed with the resilience and professionalism of the Red Cross volunteers as well as the generosity and assistance offered by those at the ex-pub (Lancing College Building). This was a horrific incident and many people witnessed what was a quite disturbing sight and a much lesser number were more immediately involved in the aftermath at the crash sight." As the afternoon wore on the public remained unable to leave the airfield until about 7pm and even then faced lengthy queues to get out as well as further delays on local roads. During this period a number of individuals came to the Red Cross treatment centre worried about the consequences of missing important medication due to being delayed in getting home and received advice from Tony.

Another SIMCAS member and Emergency Medicine Consultant, Dr Rowley Cottingham was the major incident commader at the Royal Sussex County Hospital in Brighton. He said that he was "enormously proud of the Emergency department staff and the prehospital response".
BASICS SIMCAS offer their condolences to all those affected by yesterday's tragedy and their thanks to emergency services colleagues including those of the British Red Cross and the volunteer doctors who came forward to assist.

Exulas, believe it. Above the Clouds is right.

2 notches of flap was commonly used for aeros and combat manoeuvring and it was indeed good up to 0.9M. Above that the nose down pitching moment exceeded the power in the tail plane PFCU (jack-stalling) and you ran out of pitch authority very quickly.

Things may have changed but that was how it worked last time I flew a Hunter.

The time will come, possibly as a result of this accident, that airshow aerobatic performances will have to be matched to the size of the venue to ensure any accidents remain within the airport boundary or adjacent areas clear of the public. If aerobatics can't be displayed within that area, displays might have to be be limited to flypasts and low-G turns. It would also be interesting to know if G-limited performances of warbirds to extend airframe life actually put the aircraft at greater risk by extending the diameter of loops or increasing the risk of stalls during rolling maneuvers. Rolls and loops seem to dominate in warbird airshow accidents.

Should have been a positive g maneuver , it wasn't an outside loop, from what the videos show.

He did a change of direction at the top, though, and not a simple loop. Not sure what the reason for that was.

ETA Note: this was in response to a post that appears to be gone now.

Flap Extension Speed
 

Regarding the flaps, do a google search for "Hawker Hunter (Early) F.1 discussion thread", has a lot of great photos and documents on performance. It says:
"VFE (flap extension) been 300 knots to flap 40° Otherwise Mach 0.9".
I would post the link, but when I do my posts seem to disappear... (shrug)

Regardless of flaps he surely entered that manoeuvre, whatever it was, from far too low a height. It seems he was at least level, or well below the surrounding higher ground, which is not that high. Why would you do that with so little safety margin?

The same way anyone else does, by demonstrating their competence to the CAA display evaluator.
How is the class of medical relevant?

Not of any significance to this discussion, but is that date year correct, it was at Biggin Hill.
Tootle pip!!

A friend in the serious incident chain in the area alerted me to yesterday's events via email. Tonight on the CBC National tv news in Canada we were informed Alana Cole was 'reporting on' events in England. There then followed a brief report showing pictures from Shoreham followed by one from the Prince Edward Island airshow in the Maritimes (eastern Canada) re how safe such displays were with Alana signing off from CBC Winnipeg (in the middle of Canada).....

BBC World and the 'new improved' BBC news online website were cr*p in providing details online - one had to drill down past 'world' news on both for info. Thanks to PPRuners for some balanced accounts.

Reminiscent of this famous 2003 Thunderbirds F-16 crash in Idaho:

https://www.youtube.com/watch?v=alo_XWCqNUQ

The narrator describes the maneuver as a split-s but I believe it's actually a reverse half-cuban.

I really do not think this is a reasonable comment. Generally people who are killed or injured at airshows or motor sport events have assessed the risks and accept them. Here, if I understand the situation correctly, people who had no idea that they were taking any abnormal risks at all were killed.