The Run In And Break is a joining manoeuvre, any aircraft joining should not break into the circuit until the pilot has all the other aircraft in the circuit in sight. He/she should know how many are in, as the controller normally tells him 'X aircraft ahead' at initials. This is what was the practice when I used to instruct the RIAB in military aircraft.

As the procedure is primarily designed for reducing energy prior to the downwind leg (with a secondary advantage of minimising your exposure to groundfire), it's pretty pointless in any aircraft doing less than 200 knts.

But my main point is that everyone in the circuit should know where initials is so they know where the threat is coming from if the RIAB procedure is to be used. If people don't know - then it doesn't really have a place at that airfield.

Some points:

1. This is a Military procedure carried out at Military Airfields.

2. Most if not all such Military Airfields have an ATC Service, an ATZ and thus a known traffic environment.

In the civil world, unless there is controlled airspace, it can not be taken as a known traffic environment.

Perhaps, pilots operating at uncontrolled airfields should voice their objections (if they have any) on the R/T when they hear the call "run and break".

DFC

Very true EVO with regard to FIS and A/G

However,

Why would you be doing a run and break over an airfield where you were no longer permitted to land?????

;)

DFC

This topic certainly raises temperatures. Flash why are you unwilling to name where you carry out this military joining procedure? I shall continue to exercise my privileges as a pilot and not stay in my car. I merely wish to avoid any unnecessary dangers from pilots who want to do their own thing in a circuit pattern. You can of course go to your nearest military airfield and ask if you can play at being a FL pilot there. Equally if your own airfield has no pattern traffic you may do as you wish within the rules of the airfield. To say "they cannot disallow them" is something you may wish to clarify with the airfield management.
Lawyer - I think that my concerns are that we need to avoid getting the CAA involved. The fact that some pilots need to do this in a circuit with existing traffic is surely more likely to get the CAA involved than avoiding it. As I have said above - I believe pilots should be free to do what they want BUT not where it is LIKELY to endanger others. I am a most fervant supporter of GA and believe we all have a role to play in being seen to be responsible.

Come on folk,

It is bad enough without infighting.

Having priviliges means also having responsibilities, flash. WH you will have to accept that people like doing these things and that there is a time and a place for all of this.

Can we just stick to the rules of the air and all have a slice of the cake and enjoy it.

Never done a R&B but assume they can be good fun if done in a professional manner in an aeroplane capable of doing one.

Not more red tape please.

FD

BTW are babygrows compulsory for those performing them?

Well said, Flyin'Dutch'.
No, babygrows aren't compulsory but, if you've never worn one, it won't do any harm if the instructor who demonstrates or teaches you the manoeuvre has at some point. :)

WorkingHard
It isn't the topic which has raised temperatures, but your attitude to it. I confess my reaction was influenced by reading your (now merged) thread in which you described the manoeuvre as "irresponsible behaviour", and suggested listing airfields which allow them.
The manoeuvre is not irresponsible; doing it may be, depending upon the circumstances. The idea of yet another 'ban' or restriction, whether imposed by airfields or the CAA, fills me with horror. In 30 years or so flying, I've seen an increasing number of restrictions imposed upon our freedom to use our own judgment. Some are necessary; many are an unfortunate product of the 'nanny' culture in which we now live.
There was a tragic accident at North Weald, and lessons should be learned. But I know of no evidence (personal, official or anecdotal) to suggest there is a problem calling for the imposition of yet another restriction.
Is your experience different from mine? Have you been caused anxiety by such manoeuvres?
Our attitudes are inevitably formed by the type of flying we've done - in my case, mainly RAF, Tiger Club and the Old Flying Machine Company at Duxford. Like Flash, I've frequently been invited to do a RIAB when visiting airfields. Much depends upon type flown. When flying a Harvard or Yak 11, requests are common; not surprisingly, I've never been asked when flying a Piper or Cessna. Invitation or not, I wouldn't do so unless satisfied it was safe.

I don't seek to persuade you to my point of view. Having now read many of your contributions to various topics, I am entirely satisfied the only thing we have in common is that we both hold a pilots licence. I respect your right to fly as you wish, and have done a modest amount of s&l cross-country flying myself. Some of us have a more adventurous, but nonetheless safety-conscious, approach to our flying - but there's plenty of scope for us to co-exist happily and safely without the imposition of yet more rules.

As you say FL outside aviation there are enough enemys why fight each other ?

Perhaps a knee jerk reaction to something i feel should be kept alive.

The point i'm making is accidents happen and why should a RIAB be banned after a collision. and an approach to land not be? I'm sure the approach is a bigger killer.

Like i say we take the risk.

And wannabe topguns i agree get them out the sky and onto their computers....!

I can't decide if you are a contrary fellow or you are deep sea trolling with hook and feather!

I can't wait for demo at Farnbourough. What will you be flying Flash?

...smoke me a kipper and all that jazz...

Is the R&B:

In the PPL syllabus?
In the Instructor syllabus?
Part of the CPL?
Part of the ATPL?
Described in the AIP ('Air Pilot')?
Described in CAP 413 (R/T Manual)?

No? Then perhaps you should conclude that it has no part in civil aviation and it is a military procedure. Go and do it in the military at military airfields.

I just love doing them, they are an expression of true flying in the circuit...... When done so as not to conflict with other traffic.

Maybe I also am dangerous? :eek: :eek:

Cat Driver:

Please read flying lawyers post, it makes so much sense.

Hew Jampton---- Sorry friend but there are a lot of Manoeuvres not described on your list, that I do. Does it mean I can not loop!! Shall it be illegal to practice a spin. My attempt to roll on a Sunday afternoon be a thing of the past !!!. Do a Run and Break when the circuit is clear and you are affecting no one, it is after all just another method for joining the circuit. Treat your fellow aviators with respect.

And Flash on your next R&B at least do a tight circuit or are you trying for a 747 rating :D

Love Wide

Completely agree. The problem comes when the circuit isn't clear, and people clearly still attempt R&Bs in this situation. I still do not really understand what another aeroplane would be doing if it declared that it was doing a run and break, and I bet many (if not most) PPLs are in a similar position.

IMHO, a run and break is different from aerobatics - if you fancy looping, then find a quiet bit of sky, tell whoever you are talking to what you are doing so they can tell other people to avoid you, and get on with it. A run and break is in the circuit environment. If it's empty, then fine, go ahead. If it's busy then give it a miss.

Places like North Weald aren't the problem - plan a flight there and you'll notice the warnings about high-performance aeroplanes and find out what is going on for yourself (I'd ask what they were likely to do when calling for PPR). The problem is at the places where nobody has a clue what a run and break is.

FL - I appreciate all you say and essentially we do not differ in our views of GA. My entire point was that I defend to the end a pilots right to do what is within the law and WITHOUT endangering others. I understand selective reading of a topic may draw one to the incorrect emphasis. You say quite correctly that such manoeuvres are safe at the right time and in the right place. We all seem to wholeheartedly agree with that. As you agree that a circuit that already has other traffic is not the place or time. I shall choose my form of word more carefully next time I feel strongly about an issue.
No more comment from me! (did I hear a cheer?)

Having flown military jets during training, military helicopters and light fixed wing and carried out RIABs on all of them, I see RIAB as a punchy and extroverted way of joining the circuit in an expeditious way. The origins of the manoeuvre have already been mentioned.

There are risks in the manoeuvre, tragically demonstrated by the mid-air already mentioned. However, aircraft do collide in the circuit in other circumstances that all pilots would consider more "normal", irrespective of their experience and training. For example, two gliders collided on finals whilst landing at Camphill about 4 years ago.

The common thread is insufficient lookout, with perhaps a lack of awareness by one or both pilots. As far as I was taught, it is the responsibility of the pilot joining the circuit to fit in with other traffic already in the pattern and cause no inconvenience or danger, just like road traffic joining a roundabout, or driving / flying in general.

IMHO the North Weald mid air was the fault of the Yak pilot. He failed to safely carry out a manoeuvre that was beyond the experience of the other pilot.

BTW, military airfields always have a Flying Order outlining the procedure for a RIAB, giving details of the position of "Initials", radio calls etc etc.

Hello Wide,

Sorry bout the circuit but i think the only chance i shall have of flying a 747 is in wh's world on the pc

Hopefully b flying a vulcan this year at f'bro but think there is more chance of "smoking class " being introduced on the Hindenberg

:D

I took a short video of a RIAB I did earlier on today. You can download it here;

RIAB Video

As you can see its not a particularly violent manoeuvre.
Just to note, the aircraft it is taken in is a Tutor.

ASI

Flying Lawyer got to the heart of the matter when he said

When confronted with this type of logic, is it any wonder that joe public takes the view that he doesn't give a f*ck about the semantics, just stop people in light aircraft flying over my house because it is DANGEROUS.

And there are many MPs who are only too happy to take up the anti GA cause, who understand how to argue a brief (and many of whom are or were lawyers.)

BTW, I'm not anti laywer, my own 'profession' of consultant fights for an equally lowly place in the mind of the public when asked to grade our probity.

John Fletcher Moulton said in another age that ethical behaviour was represented by 'obedience to the unenforceable.'

IMHO that's a pretty good premise for life and also RIABs.

I have been doing R & B's at my home field CYYJ for years, mostly when flying the Nanchang CJ 6 , but occassionally in a T 28 and
L 29 ( usually a high flat break ). Why do I do it ? Two reasons ; One -because its FUN ! and Two the CJ6 in particular has a very draggy gear but only a 100 kt Vle. A R & B allows me to bleed off speed and get the gear down without touching the throttle from my 550 humhugs approach manifold pressure setting . Since radial engines do not like low power high RPM/airspeed this is very desirable from a engine longevity point of view. I ask ATC for the manoever well outside the circuit and if it is not busy usually get it. The break is almost always in the opposite direction ( ie left break for the normal right hand circuit on the main runway ). As far as I know I have never bothered anybody and ATC and/or the Feds have never complained. All that been said I will not generally do R & B at a airport that does not have positive ATC.

At the end of the day I think this topic has nothing to do with the R & B it is purely an airmanship issue. Pilots that are creating problems are probably a pain in the A ** in the rest of their flying. By not behaving responsibly they are hurting th rest of us. BTW
I once overheard a PPL at my flying club disparage a nicely flown formation R & B that had just occured. He was quite vocal about how unsafe and irresponsible he considered the manoever he had just observed. We both headed out to our respective Spamcans for a local flight. Coincidentaly about a hour later we both rejoined the circuit. He was told to follow me in the downwind Number 2. I had to go around after he cut me off on final ....

ASI.........
 

Indeedy not very violent in that!

:D

FD

(Nice footage though!)

IMHO we are looking at the run and break from the worng angle.

For those who complain that they do not wish to be restricted from completing a loop or roll or spin, can I simply point out the HASELL check and remind that the "Location" must be clear of various places including active airfields.

For those who worry about having more red tape and rules, can I point out the rules of the air with regard to circuit procedures and recent CAA comments about circuit joining procedures at uncontrolled airfields.

For those who enjoy the manoeuvere, can I point out that I also do but in the correct environment.

A pilot who completes a run and break is no different from a pilot who reguluarly joins straight in on final...........no problem provided they do not affect anyone else in the circuit or cause noise complaints from the neighbours.

However, one very important point.....since a run and break is not a standard civil manoeuvere, completing one especially in response to a request or in order to impress, would require a display authorisation. Thus run and breaks will only be completed by pilots holding display authorisations.

The second very very very important point is that a run and break is not an approach to land. Thus there is no exemption from rule 5. This means that at a busy airfield, the appropriate part of rule 5 will have to be applied..................run and breaks are not so exciting when completed at or above circuit height!!..........500ft QFE is rarely an option due to man made objects.....parked aircraft, gates, water towers etc

Regards,

DFC

Final3Greens
"When confronted with this type of logic" - you've lost me. Probably my fault, but could you expand? eg Flying aerobatics is not irresponsible. Flying aerobatics over a congested area would be. Hardly just semantics? What do you mean by "this type of logic"?

DFC
I'm afraid the "very important" point in your penultimate paragraph, and the "very very very important" point in your final paragraph are both just plain wrong in law.

DFC
Two excellent points about Display Authorisation and Rule 5. It's not landing in accordance with normal (civil) aviation practice. However, FL says you are wrong, I'm sure he can quote the relevant part of the ANO/Rules or case law.

I have resited from commenting so far for various reasons...

however,

so mellowed have I become, I implore you all to ask yourselves, "Can we not all learn to live with each other?"

If someone wants to do an RIAB and it affects no one else, fine.

If somebody does an RIAB and it p!sses someone else off - fine, speak to each other on the ground.

It is encumbent upon each and every one of us to keep a good lookout - that includes in the circuit. Failure to do so might cost lifes.

I fly because I can and in this Bliar-esque nanny state I think we all really have bigger things to worry about, for fox sake someone might even start a war.

Stik - Pitts pilot who has occasionally been asked to RIAB. :)

Flying Lawyer

Sorry if I confused you - it was probably the Chateauneuf talking!

The point I was trying to make though, given the concerns in the thread about more restrictions, is that to argue a technical argument with an average red top reader NIMBY is pretty suicidal. (i.e. the manouevre isn't dangerous, the decision to do it is.) Most of our population judge what is right and wrong by standards that would last nanoseconds in court!

If the NIMBY is smart, they'll likely soon incite others by accusing us of talking 'weasel words' and spinning the case and, per Chomsky's famous statement that 'he did believe that there was a holocaust', an argument that shouldn't exist is made possible.

And it is these type of people who just want to get on with their own lives ... but can become the vox pox who galvanise the local MP, who know how to play the game etc etc.

I guess my point is that some things are best avoided and in this instance mutual common sense is the way forward, since we will all suffer if there are many more incidents like NW.

Hew J
As you know from our dealings off forum, I'm always happy to help fellow pilots if they have a specific problem. But, just like everyone else who posts on this site, I only spend time in a discussion for as long as I find it interesting/productive/enjoyable. This thread, for me at least, no longer falls into any of those categories so I'm afraid my answer will be as brief as courtesy to you permits.

See:
ANO 2000, Article 70 'Flying Displays'
Article 129 (Interpretation)
Rule 5.

I entirely agree with the rationale behind A&C's post which started this discussion, but I draw a distinction between flying a RIAB when there is other traffic to be alarmed, inconvenienced or endangered and when there is not. The former is, at best, irresponsible (+ bad airmanship) and, at worst, illegal; the latter is, IMHO, not.
Final3G doesn't care for "this type of logic" and apparently considers it to be "semantics"; he's entitled to his opinion. If anyone had suggested ignoring a rule because it cannot be enforced, his Moulton quotation would have been relevant. No-one has suggested ignoring any rule, enforceable or otherwise.

Back to the day job ................................ :D


[Edit]
F3G - just seen your post whilst checking how mine had come out ...
I didn't say "the manouevre isn't dangerous, the decision to do it is.", or anything like it. That would indeed be absurd semantics. My point throughout has been that there is nothing inherently dangerous in flying a RIAB - it depends upon the circumstances. Busy circuit = irresponsible, bad airmanship and possibly illegal by reason of endangering.
Empty circuit = not irresponsible, not bad airmanship, no 'endangering', not illegal.

The fatal at NW was tragic, but I see nothing whatsoever wrong with RIABs provided the time and place allow the manoeuvre to be flown safely. I do not accept there is a problem which needs to be addressed by the imposition of a rule - either by airfield operators or by the CAA.

FL, within a post with which I otherwise entirely agree said...

I draw a distinction between flying a RIAB when there is other traffic to be alarmed, inconvenienced or endangered and when there is not. The former is, at best, irresponsible (+ bad airmanship) and, at worst, illegal; the latter is, IMHO, not.


Surely it's far more important to be safe than within the law? The preferable position is to be both, but given a choice of safety and illegality versus an unsafe but legal action, the former should take precedent. In such events, and they do occur, case law usually sorts the anomaly out sooner or later. But where you suggest that breaking the law is the worst event, after a reduction in safety, I have to disagree.

G

FL

Sorry, I misquoted you, you said...

You seem to think that I do not like your logic.

This is not true, but what I am saying is that if the general public hear this argument IMHO it will not be received kindly.

Also the Moulton Fletcher quote was appropriate as it specifically says 'obedience to the unenforceable', which covers both aeros and RIABs when flown legally.

But it doesn't mean that it is smart to do these things 'just because you can' otherwise someone will surely argue that the privilege should be removed.

The last thing we need is more regulation, brought on by our own lack of forethought.

I don't really see what the problem is. I'm not suggesting that anything be banned, just that we all act in a mutually responsible manner.

Well past one o'clock, time for a break......
Should I look at the thread? No. I've left it.
After browsing a few other threads which interest me ....
Well perhaps just a quick look, but I won't be drawn in whatever's been posted.
Mistake!

Genghis
Of course, if circumstances are such that a choice has to be made, it's far more important to be safe than within the law. I do not consider breaking the law is worse than compromising safety, any more than I consider breaking the law is necessarily unsafe.
I thought it was clear from my various posts that I attach great importance to the safety assessment which a pilot must make if considering flying a RIAB. If it wasn't, I'm grateful to you for giving me the opportunity to clarify my position so that others don't misunderstand what I meant.

Final3G
Let's try an example away from RIABs.
Flying aerobatics over unpopulated areas is not irresponsible. Flying aerobatics over a town is.
Why would the general public hearing that argument not receive it kindly?
People argue all sorts of things, but how could anyone argue credibly that regulations should be introduced to remove our privilege to fly aeros in a safe place?
Back to RIAB:
I don't suggest it is smart to fly a RIAB 'just because you can'. I am saying there is nothing wrong with flying a RIAB unless it is done at a time and place which is unsafe, in which case there is a great deal wrong with it. ie In my opinion, provided it is executed safely (and legally) the manoeuvre is a non-issue.
"The last thing we need is more regulation, brought on by our own lack of forethought." I agree - but I don't accept that flying a safe RIAB demonstrates a lack of forethought likely to result in the introduction of more regulations.
"I don't really see what the problem is. I'm not suggesting that anything be banned, just that we all act in a mutually responsible manner." Agreed.


Makes mental note: Don't make the same mistake at the tea-time break. :)

Flying Lawyer,

I have checked out your references and agree that doing a run and break would not constitute a display thus no authorisations required.

However, with regard to Rule 5, I am not sure if I understand where you are approaching the matter from.

Let us consider that a pilot intends to complete a run and break at an airfield. The pilot descends to 500ft QFE some 1nm from the threshold and maintains that height until the upwind end of the runway whereup they complete a climbing turn to join the circuit.

Let us also consider that during the run in, the aircraft passed within 500ft of - A doubble decker bus on a road .5 mile from the airfield, A tractor near the airfield boundary and a pilot observing the action from the ground on the airfield.

Now IMHO, the run and break is not taking off or landing in accordance with normal aviation practice. (Just like closing the throttle to simulate EFATO isn't either). Thus there is no exemption to the 500ft rule available so I would consider that the pilot above infringed the rule in all three cases.

I am sure that you have better understanding of rule 5 with regard to a run and break and would like to understand where my points above are wrong.

However, leaving the legalities aside, it is very funny to compare the following and the diffeent reactions:

A.
High speed aircraft joins at high speed into the overhead, completes wide fast circuit and missed approach at the threshold consisting of level flight at 50ft along the runway before climbing to rejoin the circuit (at a lower speed).

B.
Aircraft completes the same as above and calls it a run and brerak!!

I could bet that A. would not cause any reaction while B. gets everyone worried.

DFC

DFC, RAF rules state that civvy registered aircraft shall not carry out R&B's below 500 ft QFE. In your case above (a) the obstacles mentioned would have to be directly under the aircraft or they'd be further than 500 ft away, (b) you'd need a damn accurate set of measuring equipment to prove it and (c) you're just being picky anyway :rolleyes:

FL

You stated

"I don't suggest it is smart to fly a RIAB 'just because you can'. I am saying there is nothing wrong with flying a RIAB unless it is done at a time and place which is unsafe, in which case there is a great deal wrong with it. ie In my opinion, provided it is executed safely (and legally) the manoeuvre is a non-issue."

You are, as usual, absolutely right but much of this thread is not talking about a pilot with your military training, skill, ability and experience. Nor are we dealing with the type of high performance aircraft which you fly and which not surprisingly result in requests for an R&B. [Although I do remember our immaculate RIAB at Valley several years ago in the Chipmunk being somewhat overshadowed by I think Stefan in the Gnat shortly after - it was fun from our seats but rather short on speed, noise and punch to impress those on the ground much!! :p ;) ]

God forbid that we have any more regulation but the danger is that we will unless individual pilots recognise that there is a time and a place and a second NW incident will result in the fun police stepping in. Right place, right pilot, right aircraft = brilliant fun
Wrong place, wrong pilot or wrong aircraft b#####s it up for the rest of us.

Run And breaks simply do not exist in a civilian ATC environment, we are not instructed on them are not made aware of there existence and certainly have no appropriate RT for their use.

However I would have no problem if the traffic situation permits in allowing them.

As an ATCO I believe there has to be a certain amount of flexibility, and as GA pilots fly for pleasure why not when the situation arises let them have their fun.

Wow DFC

A case of dissecting mouse turds if ever I saw one. :rolleyes:

Come on Chaps, use commonsense. If there is no one in the circuit, no noise issues and if EVERYONE know what is going on. What is the problem.

Perhaps it is not the flying it is the English. How about a 550 feet pass above the highest obstacle, for a runway inspection followed by a practice bad weather circuit. No sir it was not an R&B. It sounds a pile of rubbish, but it seems the pedants of the world would rather it so.

At the end of the day, respect fellow aviators and spend time enjoying our privileged status

Love

Wide
;)

FL

Several reasons why they may not receive it kindly, those I can think of quickly include:

1 - Some people are not rational
2 - Some people believe life is a conspiracy theory and the argument is a 'cover up'
3 - Some people are envious of rich layabouts who fly aeroplanes (see point #1)
4 - Some people are swayed by local opinion formers who incite anxiety through the 'safety' argument
5 - Some people have an environmental argument

e.g. a few months after we moved into our current house near Stansted (new build estate) a local activist knocked on the door to canvass for a petition to move the SID routes.

I asked her why and she said that local residents thought it was dangerous that airlines flew overhead.

'Wasn't the airport there when they bought their houses?' I asked.

Oh yes, she replied, but people did not realise how close the flight paths were.

In the local paper, a few weeks later, it transpires that the petition had gained several hundred supporters.

Well it got nowhere, as Stansted is ear marked for development, but all I am saying (and I am not against RIABs or aeros) is we need to act responsibly (and be seen to act responsibly) to protect our privileges.

Just an observation, but if you look at the AAIB report I think its pretty obvious that the Yak pilot did not do/was not positioning correctly for a RIAB. The implication is that he did an unauthorised flypast of his house then turned the wrong way up the base leg to reposition. If he had continued to initials, flown through deadside and broke into the downwind element of the cct at an appropriate time (having visually cleared the downwind leg) we wouldn't have been having this argument.

Regardless, as an aside, a RIAB is actually very safe as long as everyone involved knows where to look.

I was going to make the point just made by WB SATCO, but he got there first. If you fly to a field such as North Weald, Duxford, or Kemble, self briefing should indicate that some aircraft may be practising run and breaks. They may be normal (or, at least, not unusual) in a particular environment, and, as pointed out by several others above, are not inherently unsafe or inconsistent with GA. I agree, by the way, that although fun to watch and to do, they are not always needed by, for example, big pistons such as Warbirds and Yaks.

An airfield beat up on the other hand.................:p ......

Alty Meter

I'm not arguing with anyone, just pointing out that we have many powerful stakeholders outside our community.

If you are too dense to understand that public opinion may be different to pilot's opinion, then more fool you.

BTW I am the type of consultant who earns £150K pa, go figure.

Final 3 Greens
And Alty Meter is the type of pilot who earns £150K pa, so it won't take you long to figure who he flies for, or how long he's been in aviation.
Curious coincidence - I remember WorkingHard (late of this thread), and another PPL, trying to patronise professional pilots on the Mil Forum by boasting how much he earned. I say 'trying' because it only made him look very silly. Go figure. :rolleyes:

Whipping Boy's SATCO posted 18th February 2003
--------------------------------------------------------------------------------
[snip] . . . If he had continued to initials, flown through deadside and broke into the downwind element of the cct at an appropriate time (having visually cleared the downwind leg) we wouldn't have been having this argument.
[snip]

I don't think there is a dead side at North Weald when gliders are operating, because all power is one side (west of 02/20) and gliders do circuits on the other (eastern) side.

I have yet to be convinced that a RIAB at North Weald is capable of being safe unless the pilot has established that no gliders are in circuit or about to join and hence needing to land during the run in - we can't go round again! I also don't see how one can be legal if there are gliders on or near the runway unless the RIAB is carried out at least 500 feet away from them. I don't profess to know what circumstances need to be checked on the power side to make it safe from their perspective.

This is not to say that RIAB's cannot be done, simply that some checks are necessary first, just like I can't do certain things at North Weald in my glider without ascertaining first that they won't cause a problem.